Question: What is the mechanism of inflammatory response and pathogenesis of COVID-19 cases?

Title: Targeting lymphocyte Kv1.3-channels to suppress cytokine storm in severe COVID-19: Can it be a novel therapeutic strategy? Content: In the midst of a pandemic, finding effective treatments for coronavirus disease 2019 (COVID-19) is the urgent issue. In "chronic inflammatory diseases", the overexpression of delayed rectifier K+-channels (Kv1.3) in leukocytes is responsible for the overactivation of cellular immunity and the subsequent cytokine storm. In our previous basic studies, drugs including chloroquine and azithromycin strongly suppressed the channel activity and pro-inflammatory cytokine production from lymphocytes. These findings suggest a novel pharmacological mechanism by which chloroquine, with or without azithromycin, is effective for severe cases of COVID-19, in which the overactivation of cellular immunity and the subsequent cytokine storm are responsible for the pathogenesis.

Title: COVID-19 Hyperinflammation: What about Neutrophils? Content: COVID-19 is often related to hyperinflammation that drives lung or multiorgan injury. The immunopathological mechanisms that cause excessive inflammation are under investigation and constantly updated. Here, a gene network approach was used on recently published data sets to identify possible COVID-19 inflammatory mechanisms and bioactive genes. First, network analysis of putative SARS-CoV-2 cellular receptors led to the mining of a neutrophil-response signature and relevant inflammatory genes. Second, analysis of RNA-seq data sets of lung cells infected with SARS-CoV-2 revealed that infected cells expressed neutrophil-attracting chemokines. Third, analysis of RNA-seq data sets of bronchoalveolar lavage fluid cells from COVID-19 patients identified upregulation of neutrophil genes and chemokines. Different inflammatory genes mined here, including TNFR, IL-8, CXCR1, CXCR2, ADAM10, GPR84, MME, ANPEP, and LAP3, might be druggable targets in efforts to limit SARS-CoV-2 inflammation in severe clinical cases. The possible role of neutrophils in COVID-19 inflammation needs to be studied further.

Title: A dynamic immune response shapes COVID-19 progression Content: The inflammatory response to SARS-coronavirus-2 (SARS-CoV-2) infection is thought to underpin COVID-19 pathogenesis We conducted daily transcriptomic profiling of three COVID-19 cases and found that the early immune response in COVID-19 patients is highly dynamic Patient throat swabs were tested daily for SARS-CoV-2 with the virus persisting for 3-4 weeks in all three patients Cytokine analyses of whole blood revealed increased cytokine expression in the single more severe case However, most inflammatory gene expression peaked after respiratory function nadir, except those in the IL1 pathway Parallel analyses of CD4 and CD8 expression suggested that the pro-inflammatory response may be intertwined with T-cell activation that could exacerbate disease or prolong the infection Collectively, these findings hint at the possibility that IL1 and related pro-inflammatory pathways may be prognostic and serve as therapeutic targets for COVID-19 This work may also guide future studies to illuminate COVID-19 pathogenesis and develop host-directed therapies

Title: A Dynamic Immune Response Shapes COVID-19 Progression Content: The inflammatory response to SARS-coronavirus-2 (SARS-CoV-2) infection is thought to underpin COVID-19 pathogenesis. We conducted daily transcriptomic profiling of three COVID-19 cases and found that the early immune response in COVID-19 patients is highly dynamic. Patient throat swabs were tested daily for SARS-CoV-2, with the virus persisting for 3 to 4 weeks in all three patients. Cytokine analyses of whole blood revealed increased cytokine expression in the single most severe case. However, most inflammatory gene expression peaked after respiratory function nadir, except expression in the IL1 pathway. Parallel analyses of CD4 and CD8 expression suggested that the pro-inflammatory response may be intertwined with T cell activation that could exacerbate disease or prolong the infection. Collectively, these findings hint at the possibility that IL1 and related pro-inflammatory pathways may be prognostic and serve as therapeutic targets for COVID-19. This work may also guide future studies to illuminate COVID-19 pathogenesis and develop host-directed therapies.

Title: Dupilumab and COVID‐19: What should we expect? Content: Coronavirus disease 2019 (COVID‐19) is a pandemic disease caused by severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) with high morbidity and mortality. There are very limited data on the interference of immunomodulating drugs on the risk of infection and on the course of the disease. In particular, there are no current clinical data about the interference exerted by dupilumab, a biologic drugs blocking IL‐4 and IL‐13, used for adult atopic dermatitis. The pathogenesis of COVID‐19 is complex, characterized by an immune response mainly Th1/Th17. The hyper‐activation of these cells may cause the release of pro‐inflammatory cytokines that may result in lung impairment. IL‐4 and IL‐13 are Th2 cytokines, thus being part of a pathway not considered implicated in host defense mechanism against viral infections. Indeed, viral infections, including respiratory infections, have not been reported as a significant adverse event in clinical trials. Furthermore, dupilumab has been proved to be efficacious also in exacerbations of asthma, and it is known that viral infections can worsen asthma. Therefore, the current data seem to suggest that treatment with dupilumab should not be stopped during COVID‐19 pandemic. Obviously, a careful assessment is mandatory for each individual patient and further studies are necessary to characterize the immunologic responses in COVID‐19.

Title: Dupilumab and COVID-19: What should we expect? Content: Coronavirus disease 2019 (COVID-19) is a pandemic disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with high morbidity and mortality. There are very limited data on the interference of immunomodulating drugs on the risk of infection and on the course of the disease. In particular, there are no current clinical data about the interference exerted by dupilumab, a biologic drugs blocking IL-4 and IL-13, used for adult atopic dermatitis. The pathogenesis of COVID-19 is complex, characterized by an immune response mainly Th1/Th17. The hyper-activation of these cells may cause the release of pro-inflammatory cytokines that may result in lung impairment. IL-4 and IL-13 are Th2 cytokines, thus being part of a pathway not considered implicated in host defense mechanism against viral infections. Indeed, viral infections, including respiratory infections, have not been reported as a significant adverse event in clinical trials. Furthermore, dupilumab has been proved to be efficacious also in exacerbations of asthma, and it is known that viral infections can worsen asthma. Therefore, the current data seem to suggest that treatment with dupilumab should not be stopped during COVID-19 pandemic. Obviously, a careful assessment is mandatory for each individual patient and further studies are necessary to characterize the immunologic responses in COVID-19.

Title: Inflammatory and Coagulative Considerations for the Management of Orthopaedic Trauma Patients With COVID-19: A Review of the Current Evidence and Our Surgical Experience Content: Mounting evidence suggests that the pathogenesis of coronavirus disease 2019 (COVID-19) involves a hyperinflammatory response predisposing patients to thromboembolic disease and acute respiratory distress. In the setting of severe blunt trauma, damaged tissues induce a local and systemic inflammatory response through similar pathways to COVID-19. As such, patients with COVID-19 sustaining orthopaedic trauma injuries may have an amplified response to the traumatic insult because of their baseline hyperinflammatory and hypercoagulable states. These patients may have compromised physiological reserve to withstand the insult of surgical intervention before reaching clinical instability. In this article, we review the current evidence regarding pathogenesis of COVID-19 and its implications on the management of orthopaedic trauma patients by discussing a case and the most recent literature.

Title: Inflammatory and Coagulative Considerations for the Management of Orthopaedic Trauma Patients with COVID-19: A Review of the Current Evidence and Our Surgical Experience Content: Mounting evidence suggests that the pathogenesis of coronavirus disease 2019 (COVID-19) involves a hyperinflammatory response predisposing patients to thromboembolic disease and acute respiratory distress. In the setting of severe blunt trauma, damaged tissues induce a local and systemic inflammatory response through similar pathways to COVID-19. As such, patients with COVID-19 sustaining orthopaedic trauma injuries may have an amplified response to the traumatic insult due to their baseline hyperinflammatory and hypercoagulable state. These patients may have compromised physiological reserve to withstand the insult of surgical intervention before reaching clinical instability. Herein, we review the current evidence regarding pathogenesis of COVID-19 and its implications on the management of orthopaedic trauma patients by discussing a case and the most recent literature.

Title: Cytochrome P450-mediated drug interactions in COVID-19 patients: current findings and possible mechanisms Content: At the end of 2019, the entire world has witnessed the birth of a new member of coronavirus family in Wuhan, China. Ever since, the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has swiftly invaded every corner on the planet. By the end of April 2020, almost 3.5 million cases have been reported worldwide, with a death toll of about 250000 deaths. It is currently well-recognized that patient’s immune response plays a pivotal role in the pathogenesis of Coronavirus Disease 2019 (COVID-19). This inflammatory element was evidenced by its elevated mediators that, in severe cases, reach their peak in a cytokine storm. Together with the reported markers of liver injury, such hyperinflammatory state may trigger significant derangements in hepatic cytochrome P450 metabolic machinery, and subsequent modulation of drug clearance that may result in unexpected therapeutic/toxic response. We hypothesize that COVID-19 patients are potentially vulnerable to a significant disease-drug interaction, and therefore, suitable dosing guidelines with therapeutic drug monitoring should be implemented to assure optimal clinical outcomes.

Title: Dysregulation of the immune system as a driver of the critical course of the novel coronavirus disease 2019. Content: Novel coronavirus disease-2019 (COVID-19) is a highly contagious respiratory-related disease induced by the newly emerged virus SARS-CoV-2. Given that inflammatory immune cells may induce severe lung injury, the involvement of immune factors in the pathogenesis of the disease cannot be overestimated. It has been demonstrated that coronaviruses (CoVs) have developed mechanisms of immune evasion, making them invisible to the immune system at an early stage of infection. The mechanism relies on inhibition of the anti-viral response of type I interferons (IFNs), which supports uncontrolled viral replication in epithelial cells. There is growing body of evidence that the fatal hyperinflammation ('cytokine storm') responsible for the severe course of COVID-19 is a consequence of massive SARS-CoV-2 replication rather than inappropriate hyperresponsiveness of the immune system. Therefore, a dampened innate anti-viral immune response seems to be the primary cause of the delayed critical cascade of uncontrolled immune events leading to fulminating systemic inflammation. The occurrence of virus transmission even in asymptomatic subjects infected with SARS-CoV-2 clearly strengthens the evidence for a key role of sufficient immune control of viral replication in a subset of cases (e.g. in children, a population with highly effective innate immune responses). Although administration of immunomodulatory therapeutics is recommended under certain conditions in the guidelines of COVID-19 management, controversies regarding treatment protocols in immunocompromised patients infected with SARS-CoV-2 still exist. Extended knowledge of clinicians on the dysregulated immune response, which is a driver of the COVID-19 outcome, may improve both therapeutic protocols and the prognosis of SARS-CoV-2 infected patients.

Title: Dysregulation of the immune system as a driver of the critical course of the novel coronavirus disease 2019 Content: Novel coronavirus disease-2019 (COVID-19) is a highly contagious respiratory-related disease induced by the newly emerged virus SARS-CoV-2. Given that inflammatory immune cells may induce severe lung injury, the involvement of immune factors in the pathogenesis of the disease cannot be overestimated. It has been demonstrated that coronaviruses (CoVs) have developed mechanisms of immune evasion, making them invisible to the immune system at an early stage of infection. The mechanism relies on inhibition of the anti-viral response of type I interferons (IFNs), which supports uncontrolled viral replication in epithelial cells. There is growing body of evidence that the fatal hyperinflammation ('cytokine storm') responsible for the severe course of COVID-19 is a consequence of massive SARS-CoV-2 replication rather than inappropriate hyperresponsiveness of the immune system. Therefore, a dampened innate anti-viral immune response seems to be the primary cause of the delayed critical cascade of uncontrolled immune events leading to fulminating systemic inflammation. The occurrence of virus transmission even in asymptomatic subjects infected with SARS-CoV-2 clearly strengthens the evidence for a key role of sufficient immune control of viral replication in a subset of cases (e.g. in children, a population with highly effective innate immune responses). Although administration of immunomodulatory therapeutics is recommended under certain conditions in the guidelines of COVID-19 management, controversies regarding treatment protocols in immunocompromised patients infected with SARS-CoV-2 still exist. Extended knowledge of clinicians on the dysregulated immune response, which is a driver of the COVID-19 outcome, may improve both therapeutic protocols and the prognosis of SARS-CoV-2 infected patients.

Title: COVID‐19: a collision of complement, coagulation and inflammatory pathways Content: COVID‐19 is frequently accompanied by a hypercoagulable inflammatory state with microangiopathic pulmonary changes that can precede the diffuse alveolar damage characteristic of typical ARDS seen in other severe pathogenic infections. Parallels with systemic inflammatory disorders such as atypical haemolytic uraemic syndrome (aHUS) have implicated the complement pathway in the pathogenesis of COVID‐19, and particularly the anaphylatoxins C3a and C5a released from cleavage of C3 and C5 respectively. C5a is a potent cell signalling protein that activates a cytokine storm – a hyper‐inflammatory phenomenon – within hours of infection and the innate immune response. However, excess C5a can result in a pro‐inflammatory environment orchestrated through a plethora of mechanisms, that propagates lung injury, lymphocyte exhaustion and an immune paresis. Furthermore, disruption of the homeostatic interactions between complement and extrinsic and intrinsic coagulation pathways contributes to a net pro‐coagulant state in the microvasculature of critical organs. Fatal COVID‐19 has been associated with a systemic inflammatory response accompanied by a pro‐coagulant state and organ damage, particularly microvascular thrombi in the lungs and kidneys. Pathologic studies report strong evidence of complement activation. C5 blockade reduces inflammatory cytokines and their manifestations in animal studies, and has shown benefits in patients with aHUS, prompting investigation of this approach in the treatment of COVID‐19. This review describes the role of the complement pathway and particularly C5a and its aberrations in highly pathogenic virus infections, and therefore its potential as a therapeutic target in COVID‐19.

Title: COVID-19: a collision of complement, coagulation and inflammatory pathways Content: COVID-19 is frequently accompanied by a hypercoagulable inflammatory state with microangiopathic pulmonary changes that can precede the diffuse alveolar damage characteristic of typical ARDS seen in other severe pathogenic infections. Parallels with systemic inflammatory disorders such as atypical haemolytic uraemic syndrome (aHUS) have implicated the complement pathway in the pathogenesis of COVID-19, and particularly the anaphylatoxins C3a and C5a released from cleavage of C3 and C5 respectively. C5a is a potent cell signalling protein that activates a cytokine storm - a hyper-inflammatory phenomenon - within hours of infection and the innate immune response. However, excess C5a can result in a pro-inflammatory environment orchestrated through a plethora of mechanisms, that propagates lung injury, lymphocyte exhaustion and an immune paresis. Furthermore, disruption of the homeostatic interactions between complement and extrinsic and intrinsic coagulation pathways contributes to a net pro-coagulant state in the microvasculature of critical organs. Fatal COVID-19 has been associated with a systemic inflammatory response accompanied by a pro-coagulant state and organ damage, particularly microvascular thrombi in the lungs and kidneys. Pathologic studies report strong evidence of complement activation. C5 blockade reduces inflammatory cytokines and their manifestations in animal studies, and has shown benefits in patients with aHUS, prompting investigation of this approach in the treatment of COVID-19. This review describes the role of the complement pathway and particularly C5a and its aberrations in highly pathogenic virus infections, and therefore its potential as a therapeutic target in COVID-19.

Title: Thrombotic microangiopathy, DIC-syndrome and COVID-19: link with pregnancy prothrombotic state. Content: For last months, humanity has faced a formidable unknown enemy, which is presented as a new coronavirus infection. Despite the fact that the causative agents of new diseases appear at a certain frequency and that the virus SARS-CoV-2 has certain common properties with its predecessors, at the moment we are dealing with a new unknown pathogenesis of the development of severe complications in patients with risk factors. A final understanding of pathological process mechanisms is the goal of the scientific community. Summarizing research data from different countries, it became obvious that in severe cases of viral infection, we are dealing with a combination of the systemic inflammatory response syndrome, disseminated intravascular coagulation and thrombotic microangiopathy (TMA). Thrombotic microangiopathy is represented by a group of different conditions in which thrombocytopenia, hemolytic anemia, and multiple organ failure occur. The article reflects the main types of TMA, pathogenesis and principles of therapy. The main participants in the process are described in detail, including the von Willebrand factor and ADAMTS-13. Based on the knowledge available, as well as new data obtained from patients with COVID-19, we proposed possible models for the implementation of conditions such as sepsis, TMA, and DIC in patients with severe new coronavirus infection. Through a deeper understanding of pathogenesis, it will be possible to develop more effective diagnosis and therapy.

Title: Thrombotic microangiopathy, DIC-syndrome and COVID-19: link with pregnancy prothrombotic state Content: For last months, humanity has faced a formidable unknown enemy, which is presented as a new coronavirus infection. Despite the fact that the causative agents of new diseases appear at a certain frequency and that the virus SARS-CoV-2 has certain common properties with its predecessors, at the moment we are dealing with a new unknown pathogenesis of the development of severe complications in patients with risk factors. A final understanding of pathological process mechanisms is the goal of the scientific community. Summarizing research data from different countries, it became obvious that in severe cases of viral infection, we are dealing with a combination of the systemic inflammatory response syndrome, disseminated intravascular coagulation and thrombotic microangiopathy (TMA). Thrombotic microangiopathy is represented by a group of different conditions in which thrombocytopenia, hemolytic anemia, and multiple organ failure occur. The article reflects the main types of TMA, pathogenesis and principles of therapy. The main participants in the process are described in detail, including the von Willebrand factor and ADAMTS-13. Based on the knowledge available, as well as new data obtained from patients with COVID-19, we proposed possible models for the implementation of conditions such as sepsis, TMA, and DIC in patients with severe new coronavirus infection. Through a deeper understanding of pathogenesis, it will be possible to develop more effective diagnosis and therapy.

Title: The pathogenesis and treatment of the `Cytokine Storm' in COVID-19 Content: Summary Cytokine storm is an excessive immune response to external stimuli. The pathogenesis of the cytokine storm is complex. The disease progresses rapidly, and the mortality is high. Certain evidence shows that, during the coronavirus disease 2019 (COVID-19) epidemic, the severe deterioration of some patients has been closely related to the cytokine storm in their bodies. This article reviews the occurrence mechanism and treatment strategies of the COVID-19 virus-induced inflammatory storm in attempt to provide valuable medication guidance for clinical treatment.

Title: The pathogenesis and treatment of the `Cytokine Storm' in COVID-19 Content: Cytokine storm is an excessive immune response to external stimuli. The pathogenesis of the cytokine storm is complex. The disease progresses rapidly, and the mortality is high. Certain evidence shows that, during the coronavirus disease 2019 (COVID-19) epidemic, the severe deterioration of some patients has been closely related to the cytokine storm in their bodies. This article reviews the occurrence mechanism and treatment strategies of the COVID-19 virus-induced inflammatory storm in attempt to provide valuable medication guidance for clinical treatment.

Title: Viral Innate Immune Evasion and the Pathogenesis of Emerging RNA Virus Infections Content: Positive-sense single-stranded RNA (+ssRNA) viruses comprise many (re-)emerging human pathogens that pose a public health problem. Our innate immune system and, in particular, the interferon response form the important first line of defence against these viruses. Given their genetic flexibility, these viruses have therefore developed multiple strategies to evade the innate immune response in order to optimize their replication capacity. Already many molecular mechanisms of innate immune evasion by +ssRNA viruses have been identified. However, research addressing the effect of host innate immune evasion on the pathology caused by viral infections is less prevalent in the literature, though very relevant and interesting. Since interferons have been implicated in inflammatory diseases and immunopathology in addition to their protective role in infection, antagonizing the immune response may have an ambiguous effect on the clinical outcome of the viral disease. Therefore, this review discusses what is currently known about the role of interferons and host immune evasion in the pathogenesis of emerging coronaviruses, alphaviruses and flaviviruses.

Title: Pulmonary toxicity and inflammatory response of e-cigarettes containing medium-chain triglyceride oil and vitamin E acetate: Implications in the pathogenesis of EVALI but independent of SARS-COV-2 COVID-19 related proteins Content: Recently, there has been an outbreak associated with the use of e-cigarette or vaping products, associated lung injury (EVALI). The primary components of vaping products, vitamin E acetate (VEA) and medium-chain triglycerides (MCT) may be responsible for acute lung toxicity. Currently, little information is available on the physiological and biological effects of exposure to these products. We hypothesized that these e-cig cartridges and their constituents (VEA and MCT) induce pulmonary toxicity, mediated by oxidative damage and inflammatory responses, leading to acute lung injury. We studied the potential mechanisms of cartridge aerosol induced inflammatory response by evaluating the generation of reactive oxygen species by MCT, VEA, and cartridges, and their effects on the inflammatory state of pulmonary epithelium and immune cells both in vitro and in vivo. Cells exposed to these aerosols generated reactive oxygen species, caused cytotoxicity, induced epithelial barrier dysfunction, and elicited an inflammatory response. Using a murine model, the parameters of acute toxicity to aerosol inhalation were assessed. Infiltration of neutrophils and lymphocytes was accompanied by significant increases in IL-6, eotaxin, and G-CSF in the bronchoalveolar lavage fluid (BALF). In mouse plasma, eicosanoid inflammatory mediators, leukotrienes, were significantly increased. Plasma from e-cig users also showed increased levels of hydroxyeicosatetraenoic acid (HETEs) and various eicosanoids. Exposure to e-cig cartridge aerosols showed the most significant effects and toxicity compared to MCT and VEA. In addition, we determined at SARS-COV-2 related proteins and found no impact associated with aerosol exposures from these tested cartridges. Overall, this study demonstrates acute exposure to specific e-cig cartridges induces in vitro cytotoxicity, barrier dysfunction, and inflammation and in vivo mouse exposure induces acute inflammation with elevated pro-inflammatory markers in the pathogenesis of EVALI.

Title: Could hemophagocytic lymphohistiocytosis be the core issue of severe COVID-19 cases? Content: BACKGROUND: COVID-19, a disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), commonly presents as fever, cough, dyspnea, and myalgia or fatigue. Although the majority of patients with COVID-19 have mild symptoms, some are more prone to serious outcomes, including pneumonia, acute respiratory distress syndrome (ARDS), and even death. Hemophagocytic lymphohistiocytosis (HLH) is a severe, life-threatening inflammatory syndrome associated with intense cytokine release (also known as a “cytokine storm”). Similar to COVID-19, HLH is characterized by aggressive course leading to multi-organ failure. MAIN TEXT: The purpose of this review article is to draw attention to the possibility of the complication of HLH in patients with the severe course of COVID-19. Indeed, some of the clinical characteristics observed in the more severe cases of COVID-19 are reminiscent of secondary HLH (which can be triggered by infections, malignancies, rheumatological diseases, or autoimmune/immunodeficiency conditions). The pathogenesis of SARS-CoV-2 infection also suggests that HLH or a similar hyperinflammatory syndrome is the cause of the severe course of the infection. CONCLUSION: The pathogenesis and clinical symptoms of severe COVID-19 indicate that an increased inflammatory response corresponding to HLH is occurring. Therefore, patients with severe COVID-19 should be screened for hyperinflammation using standard laboratory tests to identify those for whom immunosuppressive therapy may improve outcomes.

Title: MERS-CoV infection is associated with downregulation of genes encoding Th1 and Th2 cytokines/chemokines and elevated inflammatory innate immune response in the lower respiratory tract Content: Abstract MERS-CoV, a highly pathogenic virus in humans, is associated with high morbidity and case fatality. Inflammatory responses have a significant impact on MERS-CoV pathogenesis and disease outcome. However, CD4+ T-cell induced immune responses during acute MERS-CoV infection are barely detectable, with potent inhibition of effector T cells and downregulation of antigen presentation. The local pulmonary immune response, particularly the Th1 and Th2-related immune response during acute severe MERS-CoV infection is not fully understood. In this study, we offer the first insights into the pulmonary gene expression profile of Th1 and Th2-related cytokines/chemokines (Th1 & Th2 responses) during acute MERS-CoV infection using RT2 Profiler PCR Arrays. We also quantified the expression level of primary inflammatory cytokines/chemokines. Our results showed a downregulation of Th2, inadequate (partial) Th1 immune response and high expression levels of inflammatory cytokines IL-1α and IL-1β and the neutrophil chemoattractant chemokine IL-8 (CXCL8) in the lower respiratory tract of MERS-CoV infected patients. Moreover, we identified a high viral load in all included patients. We also observed a correlation between inflammatory cytokines, Th1, and Th2 downregulation and the case fatality rate. Th1 and Th2 response downregulation, high expression of inflammatory cytokines, and high viral load may contribute to lung inflammation, severe infection, the evolution of pneumonia and ARDS, and a higher case fatality rate. Further study of the molecular mechanisms underlying the Th1 and Th2 regulatory pathways will be vital for active vaccine development and the identification of novel therapeutic strategies.

Title: Severe COVID-19: A Review of Recent Progress With a Look Toward the Future Content: The novel coronavirus disease 2019 (COVID-19) is an acute infectious disease caused by infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Currently, the World Health Organization has confirmed that COVID-19 is a global infectious disease pandemic. This is the third acute infectious disease caused by coronavirus infection in this century, after sudden acute respirator syndrome and Middle East respiratory syndrome. The damage mechanism of SARS-CoV-2 is still unclear. It is possible that protein S binds to angiotensin-converting enzyme 2 receptors and invades alveolar epithelial cells, causing direct toxic effects and an excessive immune response. This stimulates a systemic inflammatory response, thus forming a cytokine storm, which leads to lung tissue injury. In severe cases, the disease can lead to acute respiratory distress syndrome, septic shock, metabolic acidosis, coagulation dysfunction, and multiple organ dysfunction syndromes. Patients with severe COVID-19 have a relatively high mortality rate. Currently, there are no specific antiviral drugs for the treatment of COVID-19. Most patients need to be admitted to the intensive care unit for intensive monitoring and supportive organ function treatments. This article reviews the epidemiology, pathogenesis, clinical manifestations, diagnosis, and treatment methods of severe COVID-19 and puts forward some tentative ideas, aiming to provide some guidance for the diagnosis and treatment of severe COVID-19.

Title: Virus-host interactome and proteomic survey of PMBCs from COVID-19 patients reveal potential virulence factors influencing SARS-CoV-2 pathogenesis Content: The ongoing coronavirus disease (COVID-19) pandemic caused by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) is a global public health concern due to relatively easy person-to-person transmission and the current lack of effective antiviral therapy. However, the exact molecular mechanisms of SARS-CoV-2 pathogenesis remain largely unknown. We exploited an integrated proteomics approach to systematically investigate intra-viral and virus-host interactomes for the identification of unrealized SARS-CoV-2 host targets and participation of cellular proteins in the response to viral infection using peripheral blood mononuclear cells (PBMCs) isolated from COVID-19 patients. Using this approach, we elucidated 251 host proteins targeted by SARS-CoV-2 and more than 200 host proteins that are significantly perturbed in COVID-19 derived PBMCs. From the interactome, we further identified that non-structural protein nsp9 and nsp10 interact with NKRF, a NF-КB repressor, and may precipitate the strong IL-8/IL-6 mediated chemotaxis of neutrophils and overexuberant host inflammatory response observed in COVID-19 patients. Our integrative study not only presents a systematic examination of SARS-CoV-2-induced perturbation of host targets and cellular networks to reflect disease etiology, but also reveals insights into the mechanisms by which SARS-CoV-2 triggers cytokine storms and represents a powerful resource in the quest for therapeutic intervention.

Title: Suppressive myeloid cells are a hallmark of severe COVID-19 Content: 'Severe Acute Respiratory Syndrome - Coronavirus-2' (SARS-CoV-2) infection causes Coronavirus Disease 2019 (COVID-19), a mild to moderate respiratory tract infection in the majority of patients. A subset of patients, however, progresses to severe disease and respiratory failure with acute respiratory distress syndrome (ARDS). Severe COVID-19 has been associated with increased neutrophil counts and dysregulated immune responses. The mechanisms of protective immunity in mild forms and the pathogenesis of dysregulated inflammation in severe courses of COVID-19 remain largely unclear. Here, we combined two single-cell RNA-sequencing technologies and single-cell proteomics in whole blood and peripheral blood mononuclear cells (PBMC) to determine changes in immune cell composition and activation in two independent dual-center patient cohorts (n=46 + n=54 COVID-19 samples), each with mild and severe cases of COVID-19. We observed a specific increase of HLA-DR high CD11c high inflammatory monocytes that displayed a strong interferon (IFN)-stimulated gene signature in patients with mild COVID-19, which was absent in severe disease. Instead, we found evidence of emergency myelopoiesis, marked by the occurrence of immunosuppressive pre-neutrophils and immature neutrophils and populations of dysfunctional and suppressive mature neutrophils, as well as suppressive HLA-DR low monocytes in severe COVID-19. Our study provides detailed insights into systemic immune response to SARS-CoV-2 infection and it reveals profound alterations in the peripheral myeloid cell compartment associated with severe courses of COVID-19.

Title: Hyperglycemia, hydroxychloroquine, and the COVID-19 pandemic Content: Coronavirus disease-2019 (COVID-19) infection and its severity can be explained by the concentration of glycosylated severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) viral particles in the lung epithelium, the concentration of glycosylated angiotensin-converting enzyme receptor 2 (ACE2) in the lung epithelium, and the degree and control of the pulmonary immune response to the SARS-CoV-2 spike protein at approximately day 8 to 10 after symptom onset, which may be related to both. Binding of ACE2 by SARS-CoV-2 in COVID-19 also suggests that prolonged uncontrolled hyperglycemia, and not just a history of diabetes mellitus, may be important in the pathogenesis of the disease. It is tempting to consider that the same mechanism acts in COVID-19 as in SARS, where an overactive macrophage M1 inflammatory response, as neutralizing antibodies to the SARS-CoV-2 spike protein form at day 7 to 10, results in acute respiratory distress syndrome (ARDS) in susceptible patients. It also allows consideration of agents, such as hydroxychloroquine, which may interfere with this overly brisk macrophage inflammatory response and perhaps influence the course of the disease, in particular, those that blunt but do not completely abrogate the M1 to M2 balance in macrophage polarization, as well as viral load, which in SARS appears to be temporally related to the onset of ARDS.

Title: Hyperglycemia, hydroxychloroquine, and the COVID‐19 pandemic Content: Coronavirus disease‐2019 (COVID‐19) infection and its severity can be explained by the concentration of glycosylated severe acute respiratory syndrome‐coronavirus 2 (SARS‐CoV‐2) viral particles in the lung epithelium, the concentration of glycosylated angiotensin‐converting enzyme receptor 2 (ACE2) in the lung epithelium, and the degree and control of the pulmonary immune response to the SARS‐CoV‐2 spike protein at approximately day 8 to 10 after symptom onset, which may be related to both. Binding of ACE2 by SARS‐CoV‐2 in COVID‐19 also suggests that prolonged uncontrolled hyperglycemia, and not just a history of diabetes mellitus, may be important in the pathogenesis of the disease. It is tempting to consider that the same mechanism acts in COVID‐19 as in SARS, where an overactive macrophage M1 inflammatory response, as neutralizing antibodies to the SARS‐CoV‐2 spike protein form at day 7 to 10, results in acute respiratory distress syndrome (ARDS) in susceptible patients. It also allows consideration of agents, such as hydroxychloroquine, which may interfere with this overly brisk macrophage inflammatory response and perhaps influence the course of the disease, in particular, those that blunt but do not completely abrogate the M1 to M2 balance in macrophage polarization, as well as viral load, which in SARS appears to be temporally related to the onset of ARDS.

Title: The Heart and COVID-19: What Cardiologists Need to Know. Content: In face of the pandemic of the novel coronavirus disease 2019 (COVID-19), the management of patients with cardiovascular risk factors and/or disease is challenging. The cardiovascular complications evidenced in patients with COVID-19 derive from several mechanisms, ranging from direct viral injury to complications secondary to the inflammatory and thrombotic responses to the infection. The proper care of patients with COVID-19 requires special attention to the cardiovascular system aimed at better outcomes.

Title: Inflammation: A bridge between Diabetes and COVID-19, and possible management with sitagliptin Content: Patients with SARS-CoV-2 infections experience lymphopenia and inflammatory cytokine storms in the severe stage of the disease, leading to multi-organ damage. The exact pattern of immune system changes and their condition during the disease process is unclear. The available knowledge has indicated that the NF-kappa-B pathway, which is induced by several mediators, has a significant role in cytokine storm through the various mechanisms. Therefore, identifying the state of the immune cells and the dominant mechanisms for the production of cytokines incorporated in the cytokine storm can be a critical step in the therapeutic approach. On the other hand, some studies identified a higher risk for diabetic patients. Diabetes mellitus exhibits a close association with inflammation and increases the chance of developing COVID-19. Patients with diabetes mellitus have shown to have more virus entry, impaired immunity response, less viral elimination, and dysregulated inflammatory cytokines. The parallel analysis of COVID-19 and diabetes mellitus pathogenesis has proposed that the control of the inflammation through the interfering with the critical points of major signaling pathways may provide the new therapeutic approaches. In recent years, the role of Dipeptidyl Peptidase 4 (DPP4) in chronic inflammation has been proved. Numerous immune cells express the DPP4 protein. DPP4 regulates antibody production, cytokine secretion, and immunoglobulin class switching. DPP4 inhibitors like sitagliptin reduce inflammation intensity in different states. Following the accumulating data, we hypothesize that sitagliptin might reduce COVID-19 severity. Sitagliptin, an available DPP4 inhibitor drug, showed multidimensional anti-inflammatory effects among diabetic patients. It reduces the inflammation mostly by affecting on NF-kappa-B signaling pathway. Under the fact that inflammatory mediators are active in individuals with COVID-19, blocking the predominant pathway could be helpful.

Title: Overcoming Barriers: The Endothelium As a Linchpin of Coronavirus Disease 2019 Pathogenesis? Content: OBJECTIVE Coronavirus disease 2019 (COVID-19) is a global pandemic involving >5 500 000 cases worldwide as of May 26, 2020. The culprit is the severe acute respiratory syndrome coronavirus-2, which invades cells by binding to angiotensin-converting enzyme 2. While the majority of patients mount an appropriate antiviral response and recover at home, others progress to respiratory distress requiring hospital admission for supplemental oxygen. In severe cases, deterioration to acute respiratory distress syndrome necessitating mechanical ventilation, development of severe thrombotic events, or cardiac injury and dysfunction occurs. In this review, we highlight what is known to date about coronavirus disease 2019 and cardiovascular risk, focusing in on the putative role of the endothelium in disease susceptibility and pathogenesis. Approach and Results: Cytokine-driven vascular leak in the lung alveolar-endothelial interface facilitates acute lung injury in the setting of viral infection. Given that the virus affects multiple organs, including the heart, it likely gains access into systemic circulation by infecting or passing from the respiratory epithelium to the endothelium for viral dissemination. Indeed, cardiovascular complications of coronavirus disease 2019 are highly prevalent and include acute cardiac injury, myocarditis, and a hypercoagulable state, all of which may be influenced by altered endothelial function. Notably, the disease course is worse in individuals with preexisting comorbidities that involve endothelial dysfunction and may be linked to elevated ACE2 (angiotensin-converting enzyme 2) expression, such as diabetes mellitus, hypertension, and cardiovascular disease. CONCLUSIONS Rapidly emerging data on coronavirus disease 2019, together with results from studies on severe acute respiratory syndrome coronavirus-1, are providing insight into how endothelial dysfunction may contribute to the pandemic that is paralyzing the globe. This may, in turn, inform the design of biomarkers predictive of disease course, as well as therapeutics targeting pathogenic endothelial responses.

Title: Overcoming Barriers: The Endothelium As a Linchpin of Coronavirus Disease 2019 Pathogenesis? Content: OBJECTIVE: Coronavirus disease 2019 (COVID-19) is a global pandemic involving >5 500 000 cases worldwide as of May 26, 2020. The culprit is the severe acute respiratory syndrome coronavirus-2, which invades cells by binding to angiotensin-converting enzyme 2. While the majority of patients mount an appropriate antiviral response and recover at home, others progress to respiratory distress requiring hospital admission for supplemental oxygen. In severe cases, deterioration to acute respiratory distress syndrome necessitating mechanical ventilation, development of severe thrombotic events, or cardiac injury and dysfunction occurs. In this review, we highlight what is known to date about coronavirus disease 2019 and cardiovascular risk, focusing in on the putative role of the endothelium in disease susceptibility and pathogenesis. Approach and Results: Cytokine-driven vascular leak in the lung alveolar-endothelial interface facilitates acute lung injury in the setting of viral infection. Given that the virus affects multiple organs, including the heart, it likely gains access into systemic circulation by infecting or passing from the respiratory epithelium to the endothelium for viral dissemination. Indeed, cardiovascular complications of coronavirus disease 2019 are highly prevalent and include acute cardiac injury, myocarditis, and a hypercoagulable state, all of which may be influenced by altered endothelial function. Notably, the disease course is worse in individuals with preexisting comorbidities that involve endothelial dysfunction and may be linked to elevated ACE2 (angiotensin-converting enzyme 2) expression, such as diabetes mellitus, hypertension, and cardiovascular disease. CONCLUSIONS: Rapidly emerging data on coronavirus disease 2019, together with results from studies on severe acute respiratory syndrome coronavirus-1, are providing insight into how endothelial dysfunction may contribute to the pandemic that is paralyzing the globe. This may, in turn, inform the design of biomarkers predictive of disease course, as well as therapeutics targeting pathogenic endothelial responses.

Title: SARS-CoV-2 and COVID-19 in older adults: what we may expect regarding pathogenesis, immune responses, and outcomes Content: SARS-CoV-2 virus, the causative agent of the coronavirus infectious disease-19 (COVID-19), is taking the globe by storm, approaching 500,000 confirmed cases and over 21,000 deaths as of March 25, 2020. While under control in some affected Asian countries (Taiwan, Singapore, Vietnam), the virus demonstrated an exponential phase of infectivity in several large countries (China in late January and February and many European countries and the USA in March), with cases exploding by 30–50,000/day in the third and fourth weeks of March, 2020. SARS-CoV-2 has proven to be particularly deadly to older adults and those with certain underlying medical conditions, many of whom are of advanced age. Here, we briefly review the virus, its structure and evolution, epidemiology and pathogenesis, immunogenicity and immune, and clinical response in older adults, using available knowledge on SARS-CoV-2 and its highly pathogenic relatives MERS-CoV and SARS-CoV-1. We conclude by discussing clinical and basic science approaches to protect older adults against this disease.

Title: SARS-CoV-2 and COVID-19 in older adults: what we may expect regarding pathogenesis, immune responses, and outcomes Content: SARS-CoV-2 virus, the causative agent of the coronavirus infectious disease-19 (COVID-19), is taking the globe by storm, approaching 500,000 confirmed cases and over 21,000 deaths as of March 25, 2020. While under control in some affected Asian countries (Taiwan, Singapore, Vietnam), the virus demonstrated an exponential phase of infectivity in several large countries (China in late January and February and many European countries and the USA in March), with cases exploding by 30-50,000/day in the third and fourth weeks of March, 2020. SARS-CoV-2 has proven to be particularly deadly to older adults and those with certain underlying medical conditions, many of whom are of advanced age. Here, we briefly review the virus, its structure and evolution, epidemiology and pathogenesis, immunogenicity and immune, and clinical response in older adults, using available knowledge on SARS-CoV-2 and its highly pathogenic relatives MERS-CoV and SARS-CoV-1. We conclude by discussing clinical and basic science approaches to protect older adults against this disease.

Title: O Coração e a COVID-19: O que o Cardiologista Precisa Saber./ O Coração e a COVID-19: O que o Cardiologista Precisa Saber./ The Heart and COVID-19: What Cardiologists Need to Know Content: In face of the pandemic of the novel coronavirus disease 2019 (COVID-19), the management of patients with cardiovascular risk factors and/or disease is challenging. The cardiovascular complications evidenced in patients with COVID-19 derive from several mechanisms, ranging from direct viral injury to complications secondary to the inflammatory and thrombotic responses to the infection. The proper care of patients with COVID-19 requires special attention to the cardiovascular system aimed at better outcomes.

Title: A Case of Cytokine Hemofiltration and ECLS as Treatment of COVID-19 Respiratory Failure Content: Abstract Background Discovery of the novel severe acute respiratory syndrome coronavirus 2 (n-SARS-CoV-2) in late 2019 has brought with it a renewed interest in methods of inflammatory mitigation, particularly due to reports of a cytokine release syndrome playing a pathogenic role [1]. One method of decreasing inflammation is through hemofiltration in combination with a dialysis membrane that has a large cutoff for protein permeability (high-cutoff/HCO), thereby capturing inflammatory cytokines and attenuating their harmful side effects. The authors report a patient with severe acute respiratory distress syndrome (ARDS) secondary to COVID-19 infection, requiring Veno-Venous Extracorporeal Life Support (VV-ECLS) who was treated with cytokine hemofiltration and showed clinical improvement. Case Summary Our patient is a 53 year-old female who presented with coronavirus infection and respiratory failure culminating in hypoxemia refractory to conventional mechanical ventilation. She was cannulated onto veno-venous extra-corporeal life support and treated with cytokine hemofiltration using a high-cutoff filter. Following treatment, inflammatory markers improved along with compliance and oxygenation. She was decannulated from ECLS shortly thereafter. IRB approval was waived due to the single case report nature. Consent was obtained for use of images and case data. Discussion Inflammatory modulation has been theorized to be beneficial in the management of organ failure secondary to coronavirus infection. A cytokine release syndrome (CRS) has been implicated in this disease’s pathogenesis. Cytokine hemofiltration is one modality to mitigate harmful inflammation. Our patient demonstrated remarkable improvement with treatment and to our knowledge represents the first report of cytokine hemofiltration as management of COVID-19 respiratory failure in conjunction with VV-ECLS. This therapy warrants further evaluation as a treatment option.

Title: Targeting the NLRP3 Inflammasome in Severe COVID-19 Content: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a member of the genus Betacoronavirus within the family Coronaviridae. It is an enveloped single-stranded positive-sense RNA virus. Since December of 2019, a global expansion of the infection has occurred with widespread dissemination of coronavirus disease 2019 (COVID-19). COVID-19 often manifests as only mild cold-like symptomatology, but severe disease with complications occurs in 15% of cases. Respiratory failure occurs in severe disease that can be accompanied by a systemic inflammatory reaction characterized by inflammatory cytokine release. In severe cases, fatality is caused by the rapid development of severe lung injury characteristic of acute respiratory distress syndrome (ARDS). Although ARDS is a complication of SARS-CoV-2 infection, it is not viral replication or infection that causes tissue injury; rather, it is the result of dysregulated hyperinflammation in response to viral infection. This pathology is characterized by intense, rapid stimulation of the innate immune response that triggers activation of the Nod-like receptor family, pyrin domain-containing 3 (NLRP3) inflammasome pathway and release of its products including the proinflammatory cytokines IL-6 and IL-1β. Here we review the literature that describes the pathogenesis of severe COVID-19 and NLRP3 activation and describe an important role in targeting this pathway for the treatment of severe COVID-19.

Title: Pulmonary Angiotensin-Converting Enzyme 2 (ACE2) and Inflammatory Lung Disease. Content: In response to infectious and, in some instances, noninfectious insults, the affected tissues/cells of the host undergo inflammation. However, uncontrolled inflammation could be detrimental to the host, resulting in inflammatory disease, such as inflammatory lung disease. Although the etiology of the disease is well defined, the underling pathogenesis is still incompletely understood. The renin-angiotensin system (RAS), one of the primary cardiovascular regulatory systems, has been proposed to be involved in the pathogenesis of inflammatory lung disease. In particular, the RAS has been implicated as advances in the understanding of the multifunctionality of individual components of the system have been made, and by the fact that the RAS acts not only systemically, but also locally in a variety of tissues, including the lung. Angiotensin-converting enzyme 2 (ACE2), a relatively new member of the RAS, has drawn extensive attention since 2003, because of the findings that ACE2 is the receptor for SARS Corona virus and that maintenance of normal ACE2 levels in the lung is beneficial for the host to combat inflammatory lung disease. Nevertheless, the mechanism through which ACE2 plays a role in inflammatory lung disease has not been clearly identified. In an attempt to summarize current literature findings and progress made in uncovering the role of ACE2 in inflammatory lung disease, this review will focus on recent studies examining pulmonary ACE2 biology, its roles in inflammatory lung disease pathogenesis and possible underlying mechanisms. Finally, we will discuss pulmonary ACE2 as a potential therapeutic target for inflammatory lung disease.

Title: The bio-mission of interleukin-6 in the pathogenesis of COVID-19: A brief look at potential therapeutic tactics Content: Interleukin-6 (IL-6), known as an inflammatory cytokine, can be involved in many innate and adaptive immune responses. The role of IL-6 in the pathogenesis of the novel coronavirus disease 2019 (COVID-19) has recently received much more attention due to the spread of the virus and its pandemic potential. Cytokine storm is among the most critical pathological events in patients affected with coronaviruses (CoVs), i.e., severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV), and COVID-19, causing inflammation-induced lung injury and also occurring as a result of dysregulation of immune responses to the mentioned viruses. IL-6, along with some other inflammatory cytokines, including IL-1 beta (β), IL-8, and tumor necrosis factor-alpha (TNF-α), as well as inflammatory chemokines, can significantly contribute to, fever, lymphopenia, coagulation, lung injury, and multi-organ failure (MOF). Therefore, researchers are to explore novel approaches to treat the disease through targeting of IL-6 and its receptors based on prior experience of other disorders. In this review article, the latest findings on the role of IL-6 in the pathogenesis of COVID-19, as well as therapeutic perspectives, were summarized and discussed.

Title: SARS-CoV-2 and Male Infertility: Possible Multifaceted Pathology Content: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causing the coronavirus disease 2019 (COVID-19) has been declared a pandemic by the World Health Organization (WHO) on 11th March 2020. Bulk of research on this virus are carried out to unveil its multivariate pathology. Surprisingly, men are reportedly more vulnerable to COVID-19 even with higher fatality rate compared to women. Thus, it is crucial to determine whether SARS-CoV-2 infection can even affect male fertility as an immediate or long-term consequence of the disease. Among the discrete data available, an important finding is that angiotensin converting enzymes 2 (ACE2) receptor, that aids the SARS-CoV-2 entry into host cells, is profoundly expressed in testicular cells. In addition, the endogenous androgen milieu and its receptors are associated with ACE2 activation reflecting that enhanced testosterone levels may trigger the pathogenesis of COVID-19. In contrary, hypogonadism has also been reported in the acute phase of some COVID-19 cases. Moreover, SARS-CoV-2 infection-induced uncontrolled inflammatory responses may lead to systemic oxidative stress (OS), whose severe disruptive effects on testicular functions are well-documented. This article aims to precisely present the possible impact of COVID-19 on male reproductive functions, and to highlight the speculations that need in-depth research for the exact underlying mechanisms how COVID-19 is associated with men's health and fertility.

Title: SARS-CoV-2 and Male Infertility: Possible Multifaceted Pathology Content: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causing the coronavirus disease 2019 (COVID-19) has been declared a pandemic by the World Health Organization (WHO) on 11th March 2020. Bulk of research on this virus are carried out to unveil its multivariate pathology. Surprisingly, men are reportedly more vulnerable to COVID-19 even with higher fatality rate compared to women. Thus, it is crucial to determine whether SARS-CoV-2 infection can even affect male fertility as an immediate or long-term consequence of the disease. Among the discrete data available, an important finding is that angiotensin converting enzymes 2 (ACE2) receptor, that aids the SARS-CoV-2 entry into host cells, is profoundly expressed in testicular cells. In addition, the endogenous androgen milieu and its receptors are associated with ACE2 activation reflecting that enhanced testosterone levels may trigger the pathogenesis of COVID-19. In contrary, hypogonadism has also been reported in the acute phase of some COVID-19 cases. Moreover, SARS-CoV-2 infection-induced uncontrolled inflammatory responses may lead to systemic oxidative stress (OS), whose severe disruptive effects on testicular functions are well-documented. This article aims to precisely present the possible impact of COVID-19 on male reproductive functions, and to highlight the speculations that need in-depth research for the exact underlying mechanisms how COVID-19 is associated with men’s health and fertility.

Title: Mechanisms of Virus-Induced Airway Immunity Dysfunction in the Pathogenesis of COPD Disease, Progression, and Exacerbation Content: Chronic obstructive pulmonary disease (COPD) is the integrated form of chronic obstructive bronchitis and pulmonary emphysema, characterized by persistent small airway inflammation and progressive irreversible airflow limitation. COPD is characterized by acute pulmonary exacerbations and associated accelerated lung function decline, hospitalization, readmission and an increased risk of mortality, leading to huge social-economic burdens. Recent evidence suggests ~50% of COPD acute exacerbations are connected with a range of respiratory viral infections. Nevertheless, respiratory viral infections have been linked to the severity and frequency of exacerbations and virus-induced secondary bacterial infections often result in a synergistic decline of lung function and longer hospitalization. Here, we review current advances in understanding the cellular and molecular mechanisms underlying the pathogenesis of COPD and the increased susceptibility to virus-induced exacerbations and associated immune dysfunction in patients with COPD. The multiple immune regulators and inflammatory signaling pathways known to be involved in host-virus responses are discussed. As respiratory viruses primarily target airway epithelial cells, virus-induced inflammatory responses in airway epithelium are of particular focus. Targeting virus-induced inflammatory pathways in airway epithelial cells such as Toll like receptors (TLRs), interferons, inflammasomes, or direct blockade of virus entry and replication may represent attractive future therapeutic targets with improved efficacy. Elucidation of the cellular and molecular mechanisms of virus infections in COPD pathogenesis will undoubtedly facilitate the development of these potential novel therapies that may attenuate the relentless progression of this heterogeneous and complex disease and reduce morbidity and mortality.

Title: Covid-19: A systemic disease treated with a wide-ranging approach: A case report. Content: At the end of December 2019, the Health Commission of the city of Wuhan, China, alerted the World Health Organization (WHO) to a pneumonia cluster in the city. The cause was identified as being a new virus, later named SARS-CoV-2. We can distinguish three clinical phases of the disease with a distinct pathogenesis, manifestations and prognosis. Here, we describe the case of a 45-year-old male, successfully treated for Coronavirus disease (COVID-19). The patient was feeling sick in early April 2020; he had a fever and pharyngodynia. When he came to our COVID hospital, his breathing was normal. The nasopharyngeal swab specimen turned out positive. High-resolution computed tomography (HRCT) showed mild interstitial pneumonia. The patient was admitted to our department and treated with hydroxychloroquine, ritonavir, darunavir, azithromycin and enoxaparin. On day seven of the disease, the patient's respiratory condition got worse as he was developing acute respiratory distress syndrome (ARDS). He was given tocilizumab and corticosteroids and was immediately treated with non-invasive mechanical ventilation (NIMV). His condition improved, and in the ensuing days, the treatment gradually switched to a high-flow nasal cannula (HFNC); after 18 days, the patient's clinical condition was good.The successful results we have been able to obtain are closely associated with avoidance of invasive ventilation that may lead to intensive care unit (ICU)-related superinfections. In our opinion, it is fundamental to understand that COVID-19 is a systemic disease that is a consequence of an overwhelming inflammatory response, which can cause severe medical conditions, even in young patients.

Title: Covid-19: A systemic disease treated with a wide-ranging approach: A case report Content: At the end of December 2019, the Health Commission of the city of Wuhan, China, alerted the World Health Organization (WHO) to a pneumonia cluster in the city. The cause was identified as being a new virus, later named SARS-CoV-2. We can distinguish three clinical phases of the disease with a distinct pathogenesis, manifestations and prognosis. Here, we describe the case of a 45-year-old male, successfully treated for Coronavirus disease (COVID-19). The patient was feeling sick in early April 2020; he had a fever and pharyngodynia. When he came to our COVID hospital, his breathing was normal. The nasopharyngeal swab specimen turned out positive. High-resolution computed tomography (HRCT) showed mild interstitial pneumonia. The patient was admitted to our department and treated with hydroxychloroquine, ritonavir, darunavir, azithromycin and enoxaparin. On day seven of the disease, the patient's respiratory condition got worse as he was developing acute respiratory distress syndrome (ARDS). He was given tocilizumab and corticosteroids and was immediately treated with non-invasive mechanical ventilation (NIMV). His condition improved, and in the ensuing days, the treatment gradually switched to a high-flow nasal cannula (HFNC); after 18 days, the patient's clinical condition was good.The successful results we have been able to obtain are closely associated with avoidance of invasive ventilation that may lead to intensive care unit (ICU)-related superinfections. In our opinion, it is fundamental to understand that COVID-19 is a systemic disease that is a consequence of an overwhelming inflammatory response, which can cause severe medical conditions, even in young patients.

Title: Immuno-pathogenesis of nCOVID-19 and a possible host-directed therapy including anti-inflammatory and anti-viral prostaglandin (PG J(2)) for effective treatment and reduce the death toll Content: Coronaviruses including severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2, also known as 2019-nCoV especially in China) replicate and divide in host cell. During this they are partly hidden from the innate immune responses although inflammatory consequences of viral replication still occur. We propose that anti-inflammatory antiviral prostaglandins may not only restrict viral replication but can also prevent inflammatory responses in the lungs and other vital organs that are known to be part of the immuno-pathogenesis of coronavirus disease-19 (COVID-19). The combination of anti-inflammatory antiviral prostaglandins with interferons may lead to the clearance of viruses inside the growth-restricted infected cells. However, further experimental studies and clinical trials should be conducted to evaluate the safety and efficacy of these possible therapies.

Title: New spectrum of COVID-19 manifestations in children: Kawasaki-like syndrome and hyperinflammatory response Content: Since late April 2020, data regarding Kawasaki-like syndrome and hyperinflammatory response in children associated with COVID-19 has rapidly emerged. Much remains unknown about the risk factors, pathogenesis, prognosis, and specific therapy for this emerging manifestation of COVID-19 known as Multisystem Inflammatory Syndrome in Children (MIS-C). MIS-C is rare and early recognition is crucial though no standardized treatment guideline have been established. Worldwide collaboration will be important as more cases are recognized going forward.

Title: New spectrum of COVID-19 manifestations in children: Kawasaki-like syndrome and hyperinflammatory response. Content: Since late April 2020, data regarding Kawasaki-like syndrome and hyperinflammatory response in children associated with COVID-19 has rapidly emerged. Much remains unknown about the risk factors, pathogenesis, prognosis, and specific therapy for this emerging manifestation of COVID-19 known as Multisystem Inflammatory Syndrome in Children (MIS-C). MIS-C is rare and early recognition is crucial though no standardized treatment guideline have been established. Worldwide collaboration will be important as more cases are recognized going forward.

Title: Pathophysiology of viral-induced exacerbations of COPD Content: Inflammation of the lower airways is a central feature of chronic obstructive pulmonary disease (COPD). Inflammatory responses are associated with an increased expression of a cascade of proteins including cytokines, chemokines, growth factors, enzymes, adhesion molecules and receptors. In most cases the increased expression of these proteins is the result of enhanced gene transcription: many of these genes are not expressed in normal cells under resting conditions but they are induced in the inflammatory process in a cell-specific manner. Transcription factors regulate the expression of many pro-inflammatory genes and play a key role in the pathogenesis of airway inflammation. Many studies have suggested a role for viral infections as a causative agent of COPD exacerbations. In this review we will focus our attention on the relationship between common respiratory viral infections and the molecular and inflammatory mechanisms that lead to COPD exacerbation.

Title: A close-up on COVID-19 and cardiovascular diseases Content: AIMS: To analyze the potential mechanism of cardiovascular dysfunctions induced by Coronavirus Disease 2019 (COVID-19) and to evaluate more effective therapeutic pathways for patients with cardiovascular diseases. DATA SYNTHESIS: COVID-19 mainly invades the lungs, causing its serious damage. Studies found that COVID-19 induced the renin-angiotensin system imbalance, inflammatory storm, hypoxemia, stress response, and so on; all contributed to hypertension and serious myocardial damage in the process of virus pathogenesis, even increasing mortality in COVID-19 patients. CONCLUSION: In the process of management of COVID-19 infections, close attention should be paid on both lung and cardiovascular damage, especially on those with only symptoms of cardiovascular diseases. Early identification, timely and effective treatments, and maintenance of hemodynamics and electrophysiological stability are of great significance on effective treatment and long-term prognosis.

Title: COVID-19: pathogenesis, genetic polymorphism, clinical features and laboratory findings Content: COVID-19 caused by a novel agent SARS-CoV-2 progressed to a pandemic condition and resulted in a major public health concern worldwide, leading to social and economic issues at the same time. The pathogenesis of COVID-19 starts with the bonding of the virus to ACE2 receptors expressed in many tissues, and the triggered excessive immune response plays a critical role in the course of the disease. The cytokine storm that occurs upon excessive production of pro-inflammatory cytokines is considered responsible for the severe progression of the disease and the organ damage. However, the accurate pathophysiological mechanism of the disease, which progresses with various clinical presentations, is still substantially unknown. While various studies have been conducted on the effect of genetic polymorphism on the course and severity of the disease, the presence of a significant effect has not been proven yet. The clinical course of the disease is variable, with clinical representation ranging from 81% mild course to 14% severe course along with 5% critical course in patients. Asymptomatic course is considered to be higher than expected, although its frequency is not known exactly. Older adults and those with comorbidities are exposed to a more severe disease course. The disease progress with various symptoms, such as fever, cough, dyspnea, malaise, myalgia, taste and smell dysfunctions, diarrhea, and headache. A range of complications (acute respiratory distress syndrome, thromboembolic conditions, arrhythmia and cardiac events, secondary infections) could be seen during the course of the disease. Varied laboratory tests are vital to determine these verity and prognosis of the disease, along with the condition and exposure of the affected systems during thecourse of COVID-19.

Title: COVID-19: Pathogenesis, Genetic Polymorphism, Clinical Features and Laboratory Findings. Content: COVID-19 caused by a novel agent SARS-CoV-2 progressed to a pandemic condition and resulted in a major public health concern worldwide, leading to social and economic issues at the same time. The pathogenesis of COVID-19 starts with the bonding of the virus to ACE-2 receptors expressed in many tissues, and the triggered excessive immune response plays a critical role in the course of the disease. The cytokine storm that occurs upon excessive production of pro-inflammatory cytokines is considered responsible for the severe progression of the disease and the organ damage. However, the accurate pathophysiological mechanism of the disease, which progresses with various clinical presentations, is still substantially unknown. While various studies have been conducted on the effect of genetic polymorphism on the course and severity of the disease, the presence of a significant effect has not been proven yet. The clinical course of the disease is variable, with clinical representation ranging from 81% mild course to 14% severe course along with 5% critical course in patients. Asymptomatic course is considered to be higher than expected, although its frequency is not known exactly. Older adults and those with comorbidities are exposed to a more severe disease course. The disease progress with various symptoms, such as fever, cough, dyspnea, malaise, myalgia, taste and smell dysfunctions, diarrhea, and headache. A range of complications (Acute Respiratory Distress Syndrome, thromboembolic conditions, arrhythmia and cardiac events, secondary infections) could be seen during the course of the disease. Varied laboratory tests are vital to determine the severity and prognosis of the disease, along with the condition and exposure of the affected systems during the course of COVID-19.

Title: Operation of mitochondrial machinery in viral infection-induced immune responses Content: Abstract Mitochondria have been recognized as ancient bacteria that contain evolutionary endosymbionts. Metabolic pathways and inflammatory signals interact within mitochondria in response to different stresses, such as viral infections. In this commentary, we address several interesting questions, including (1) how do mitochondrial machineries participate in immune responses; (2) how do mitochondria mediate antiviral immunity; (3) what mechanisms involved in mitochondrial machinery, including the downregulation of mitochondrial DNA (mtDNA), disturbances of mitochondrial dynamics, and the induction of mitophagy and regulation of apoptosis, have been adopted by viruses to evade antiviral immunity; (4) what mechanisms involve the regulation of mitochondrial machineries in antiviral therapeutics; and (5) what are the potential challenges and perspectives in developing mitochondria-targeting antiviral treatments? This commentary provides a comprehensive review of the roles and mechanisms of mitochondrial machineries in immunity, viral infections and related antiviral therapeutics.

Title: SARS-CoV-2 Infection of Pluripotent Stem Cell-derived Human Lung Alveolar Type 2 Cells Elicits a Rapid Epithelial-Intrinsic Inflammatory Response Content: The most severe and fatal infections with SARS-CoV-2 result in the acute respiratory distress syndrome, a clinical phenotype of coronavirus disease 2019 (COVID-19) that is associated with virions targeting the epithelium of the distal lung, particularly the facultative progenitors of this tissue, alveolar epithelial type 2 cells (AT2s). Little is known about the initial responses of human lung alveoli to SARS-CoV-2 infection due in part to inability to access these cells from patients, particularly at early stages of disease. Here we present an in vitro human model that simulates the initial apical infection of the distal lung epithelium with SARS-CoV-2, using AT2s that have been adapted to air-liquid interface culture after their derivation from induced pluripotent stem cells (iAT2s). We find that SARS-CoV-2 induces a rapid global transcriptomic change in infected iAT2s characterized by a shift to an inflammatory phenotype predominated by the secretion of cytokines encoded by NF-kB target genes, delayed epithelial interferon responses, and rapid loss of the mature lung alveolar epithelial program. Over time, infected iAT2s exhibit cellular toxicity that can result in the death of these key alveolar facultative progenitors, as is observed in vivo in COVID-19 lung autopsies. Importantly, drug testing using iAT2s confirmed the efficacy of TMPRSS2 protease inhibition, validating putative mechanisms used for viral entry in human alveolar cells. Our model system reveals the cell-intrinsic responses of a key lung target cell to infection, providing a platform for further drug development and facilitating a deeper understanding of COVID-19 pathogenesis.

Title: Identification and Analysis of Shared Risk Factors in Sepsis and High Mortality Risk COVID-19 Patients Content: BACKGROUND Coronavirus disease 2019 (COVID-19) is a novel coronavirus strain disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The disease is highly transmissible and severe disease including viral sepsis has been reported in up to 16% of hospitalized cases. The admission characteristics associated with increased odds of hospital mortality among confirmed cases of COVID-19 include severe hypoxia, low platelet count, elevated bilirubin, hypoalbuminemia and reduced glomerular filtration rate. These symptoms correlate highly with severe sepsis cases. The diseases also share similar co-morbidity risks including dementia, type 2 diabetes mellitus, coronary heart disease, hypertension and chronic renal failure. Sepsis has been observed in up to 59% of hospitalized COVID-19 patients. It is highly desirable to identify risk factors and novel therapy/drug repurposing avenues for late-stage severe COVID-19 patients. This would enable better protection of at-risk populations and clinical stratification of COVID-19 patients according to their risk for developing life threatening disease. METHODS As there is currently insufficient data available for confirmed COVID-19 patients correlating their genomic profile, disease severity and outcome, co-morbidities and treatments as well as epidemiological risk factors (such as ethnicity, blood group, smoking, BMI etc.), a direct study of the impact of host genomics on disease severity and outcomes is not yet possible. We therefore ran a study on the UK Biobank sepsis cohort as a surrogate to identify sepsis associated signatures and genes, and correlated these with COVID-19 patients. Sepsis is itself a life-threatening inflammatory health condition with a mortality rate of approximately 20%. Like the initial studies for COVID-19 patients, standard genome wide association studies (GWAS) have previously failed to identify more than a handful of genetic variants that predispose individuals to developing sepsis. RESULTS We used a combinatorial association approach to analyze a sepsis population derived from UK Biobank. We identified 70 sepsis risk-associated genes, which provide insights into the disease mechanisms underlying sepsis pathogenesis. Many of these targets can be grouped by common mechanisms of action such as endothelial cell dysfunction, PI3K/mTOR pathway signaling, immune response regulation, aberrant GABA and neurogenic signaling. CONCLUSION This study has identified 70 sepsis related genes, many of them for the first time, that can reasonably be considered to be potentially relevant to severe COVID-19 patients. We have further identified 59 drug repurposing candidates for 13 of these targets that can be used for the development of novel therapeutic strategies to increase the survival rate of patients who develop sepsis and potentially severe COVID-19.

Title: Natural killer cell activation related to clinical outcome of COVID-19 Content: Understanding innate immune responses in COVID-19 is important for deciphering mechanisms of host responses and interpreting disease pathogenesis. Natural killer (NK) cells are innate effector lymphocytes that respond to acute viral infections, but might also contribute to immune pathology. Here, using 28-color flow cytometry, we describe a state of strong NK cell activation across distinct subsets in peripheral blood of COVID-19 patients, a pattern mirrored in scRNA-seq signatures of lung NK cells. Unsupervised high-dimensional analysis identified distinct immunophenotypes that were linked to disease severity. Hallmarks of these immunophenotypes were high expression of perforin, NKG2C, and Ksp37, reflecting a high presence of adaptive NK cell expansions in circulation of patients with severe disease. Finally, arming of CD56bright NK cells was observed in course of COVID-19 disease states, driven by a defined protein-protein interaction network of inflammatory soluble factors. This provides a detailed map of the NK cell activation-landscape in COVID-19 disease.

Title: No indications for overt innate immune suppression in critically ill COVID-19 patients Content: At the end of March 2020, there were in excess of 800.000 confirmed cases of coronavirus disease 2019 (COVID-19) worldwide. Several reports suggest that, in severe cases, COVID-19 may cause a hyperinflammatory 'cytokine storm'. However, unlike SARS-CoV infection, high levels of anti-inflammatory mediators have also been reported in COVID-19 patients. One study reported that 16% of COVID-19 patients who died developed secondary infection, which might indicate an immune-suppressed state. We explored kinetics of mHLA-DR expression, the most widely used marker of innate immune suppression in critically ill patients, in COVID-19 patients admitted to the ICU. Twenty-four confirmed COVID-19 patients were included, of which 75% was male and 79% had comorbidities. All patients were mechanically ventilated and exhibited large high levels of inflammatory parameters such as CRP and PCT. mHLA-DR expression levels were mostly within the normal range of 15000 - 45000 mAb/cell and showed no change over time. COVID-19 patients displayed notably higher mHLA-DR expression levels compared with bacterial septic shock patients. None of the COVID-19 patients developed a secondary infection. In conclusion, despite a pronounced inflammatory response, mHLA-DR expression kinetics indicate no overt innate immune suppression in COVID-19 patients. These data signify that innate immune suppression as a negative feedback mechanism following PAMP-induced inflammation appears not to be present in COVID-19.

Title: Comprehensive Transcriptomic Analysis of COVID-19 Blood, Lung, and Airway Content: Abstract SARS-CoV2 is a previously uncharacterized coronavirus and causative agent of the COVID-19 pandemic. The host response to SARS-CoV2 has not yet been fully delineated, hampering a precise approach to therapy. To address this, we carried out a comprehensive analysis of gene expression data from the blood, lung, and airway of COVID-19 patients. Our results indicate that COVID-19 pathogenesis is driven by populations of myeloid-lineage cells with highly inflammatory but distinct transcriptional signatures in each compartment. The relative absence of cytotoxic cells in the lung suggests a model in which delayed clearance of the virus may permit exaggerated myeloid cell activation that contributes to disease pathogenesis by the production of inflammatory mediators. The gene expression profiles also identify potential therapeutic targets that could be modified with available drugs. The data suggest that transcriptomic profiling can provide an understanding of the pathogenesis of COVID-19 in individual patients. Graphical Abstract

Title: Cardiovascular Impairment in COVID-19: Learning From Current Options for Cardiovascular Anti-Inflammatory Therapy Content: In December 2019, Coronavirus Disease 2019 (COVID-19) caused by SARS-CoV-2, occurred in China and has currently led to a global pandemic. In addition to respiratory involvement, COVID-19 was also associated with significant multiple organ dysfunction syndrome (MODS). Cardiovascular impairment has been observed and is now drawing growing attention. Cardiovascular protective strategies are urgent and of great significance to the overall prognosis of COVID-19 patients. Direct viral infection, cytokine storm, and aggravation of existing cardiovascular diseases were recognized as possible mechanisms of cardiovascular impairment in COVID-19. Hyperactivated inflammation plays an important role in all three mechanisms and is considered to be fundamental in the development of cardiovascular impairment and MODS in COVID-19. Therefore, in addition to conventional cardiovascular treatment, anti-inflammatory therapy is a reasonable strategy for severe cases to further enhance cardiovascular protection and potentially mitigate MODS. We reviewed the inflammatory features and current promising treatments of COVID-19 as well as cardiovascular anti-inflammatory therapies that have been verified in previous clinical trials with positive outcomes. We believe that targeting the central pathway (IL-1β, TNF-α, IL-6), balancing the Th1 and Th2 response, and administering long-term anti-inflammatory therapy might be promising prospects to reduce cardiovascular impairment and even MODS during the acute and recovery phases of COVID-19. The cardiovascular anti-inflammatory therapies might be of great application value to the management of COVID-19 patients and we further propose an algorithm for the selection of anti-inflammatory therapy for COVID-19 patients with or at high risk of cardiovascular impairment. We recommend to take the experiences in cardiovascular anti-inflammatory therapy as references in the management of COVID-19 and conduct related clinical trials, while the clinical translation of novel treatments from preclinical studies or in vitro drug screening should proceed with caution due to unguaranteed efficacy and safety profiles.

Title: An Insight into the Sex Differences in COVID-19 Patients: What are the Possible Causes? Content: Studies have reported a sex bias in case fatalities of COVID-19 patients. Moreover, it is observed that men have a higher risk of developing a severe form of the disease compared to women, highlighting the importance of disaggregated data of male and female COVID-19 patients. On the other hand, other factors (eg, hormonal levels and immune functions) also need to be addressed due to the effects of sex differences on the outcomes of COVID-19 patients. An insight into the underlying causes of sex differences in COVID-19 patients may provide an opportunity for better care of the patients or prevention of the disease. The current study reviews the reports concerning with the sex differences in COVID-19 patients. It is explained how sex can affect angiotensin converting enzyme-2 (ACE2), that is a key component for the pathogenesis of COVID-19, and summarized the gender differences in immune responses and how sex hormones are involved in immune processes. Furthermore, the available data about the impact of sex hormones on the immune functions of COVID-19 cases are looked into.

Title: Hepatic involvement in COVID-19 patients: pathology, pathogenesis and clinical implications [Review]. Content: During the clinical course of COVID-19, it has been observed that hepatic injury occurs in a significant proportion of patients, particularly in those with severe or critical illness. Mild increase in sinusoidal lymphocytic infiltration and multifocal hepatic necrosis are the main pathologic changes. Direct viral induced cellular injuries and potential hepatotoxicity from therapeutic drugs are two likely underlying mechanisms. In addition, preexisting chronic liver disease exacerbated during COVID-19, and COVID-19-related hyper-inflammatory reactions may contribute to liver injury as well. Further studies of additional autopsy cases will help clarifying these possibilities. This article is protected by copyright. All rights reserved.

Title: Role of Regulatory T Cells in Pathogenesis and Biological Therapy of Multiple Sclerosis Content: Multiple sclerosis (MS) is an inflammatory disease in which the myelin sheaths around the axons of the brain and spinal cord are damaged, leading to demyelination and scarring as well as a broad spectrum of signs and symptoms. It is caused by an autoimmune response to self-antigens in a genetically susceptible individual induced by unknown environmental factors. Principal cells of the immune system that drive the immunopathological processes are T cells, especially of T(H)1 and T(H)17 subsets. However, in recent years, it was disclosed that regulatory T cells took part in, too. Subsequently, there was endeavour to develop ways how to re-establish their physiological functions. In this review, we describe known mechanisms of action, efficacy, and side-effects of contemporary and emerging MS immunotherapeutical agents on Treg cells and other cells of the immune system involved in the immunopathogenesis of the disease. Furthermore, we discuss how laboratory immunology can offer physicians its help in the diagnosis process and decisions what kind of biological therapy should be used.

Title: COVID-19. Immunothrombosis and the gastrointestinal tract Content: Mönkemüller et al. brilliantly describe the pathogenesis of SARS-CoV-2 (COVID-19) in the gastrointestinal tract. Their findings highlight the local and systemic inflammatory response generated by the coronavirus. After having the opportunity to observe three cases of severe colonic ischemia and elevation of D-dimer levels in patients with COVID-19 and severe acute respiratory distress syndrome (SARS) due to SARS-CoV-2, we would like to highlight the thromboembolic complications in COVID-19, which are related to those reported by Mönkemüller and which have been mentioned by other authors.

Title: COVID-19. Immunothrombosis and the gastrointestinal tract. Content: Mönkemüller et al. brilliantly describe the pathogenesis of SARS-CoV-2 (COVID-19) in the gastrointestinal tract. Their findings highlight the local and systemic inflammatory response generated by the coronavirus. After having the opportunity to observe three cases of severe colonic ischemia and elevation of D-dimer levels in patients with COVID-19 and severe acute respiratory distress syndrome (SARS) due to SARS-CoV-2, we would like to highlight the thromboembolic complications in COVID-19, which are related to those reported by Mönkemüller and which have been mentioned by other authors.

Title: Delirium in COVID-19: A case series and exploration of potential mechanisms for central nervous system involvement Content: INTRODUCTION: Neuropsychiatric manifestations of the coronavirus disease 2019 (COVID-19) have been described, including anosmia, ageusia, headache, paresthesia, encephalitis and encephalopathy. Little is known about the mechanisms by which the virus causes central nervous system (CNS) symptoms, and therefore little guidance is available regarding potential workup or management options. CASES: We present a series of four consecutive cases, seen by our psychiatry consultation service over a one-week period, each of which manifested delirium as a result of infection with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). DISCUSSION: The four cases highlighted here all occurred in older patients with premorbid evidence of cognitive decline. Unique features seen in multiple cases included rigidity, alogia, abulia, and elevated inflammatory markers. In all four cases, a change in mental status was the presenting symptom, and three of the four cases lacked significant respiratory symptoms. In addition to discussing unique features of the cases, we discuss possible pathophysiologic explanations for COVID-19 delirium. CONCLUSIONS: Delirium should be recognized as a potential feature of infection with SARS-CoV-2 and may be the only presenting symptom. Based on the high rates of delirium demonstrated in prior studies, hospitals should consider adding mental status changes to the list of testing criteria. Further research is needed to determine if delirium in COVID-19 represents a primary encephalopathy heralding invasion of the CNS by the virus, or a secondary encephalopathy related to systemic inflammatory response or other factors.

Title: The role of antigen-presenting cells in filoviral hemorrhagic fever: gaps in current knowledge Content: The filoviruses, ebolavirus (EBOV) and marburgvirus (MARV), are highly lethal zoonotic agents of concern as emerging pathogens and potential bioweapons. Antigen-presenting cells (APCs), particularly macrophages and dendritic cells, are targets of filovirus infection in vivo. Infection of these cell types has been proposed to contribute to the inflammation, activation of coagulation cascades and ineffective immune responses characteristic of filovirus hemorrhagic fever. However, many aspects of filovirus-APC interactions remain to be clarified. Among the unanswered questions: What determines the ability of filoviruses to replicate in different APC subsets? What are the cellular signaling pathways that sense infection and lead to production of copious quantities of cytokines, chemokines and tissue factor? What are the mechanisms by which innate antiviral responses are disabled by these viruses, and how may these mechanisms contribute to inadequate adaptive immunity? A better understanding of these issues will clarify the pathogenesis of filoviral hemorrhagic fever and provide new avenues for development of therapeutics.

Title: Pharmacological agents under investigation in the treatment of coronavirus disease 2019 and the importance of melatonin Content: Coronavirus disease 2019 (COVID-19) is a life-threatening infectious respiratory disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). COVID-19 pandemic causing morbidities and even deaths worldwide revealed that there is urgent need to find pharmacological agents or vaccines. Although there are a lot of agents under investigation, there is no approved agent for the prevention or treatment of the COVID-19 yet. Treatment of patients remains mainly supportive as well as compassionate use of the agents under investigation. It is well established that excessive inflammatory and immune response as well as oxidative injury play a critical role in the pathogenesis of COVID-19. In this review, we aimed to update knowledge about pathogenesis, clinical features and pharmacological treatment of COVID-19 and review the potential beneficial effects of ancient antioxidant, anti-inflammatory and immunomodulatory molecule melatonin for prevention and treatment of COVID-19.

Title: Pharmacological agents under investigation in the treatment of coronavirus disease 2019 and the importance of melatonin. Content: Coronavirus disease 2019 (COVID-19) is a life-threatening infectious respiratory disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). COVID-19 pandemic causing morbidities and even deaths worldwide revealed that there is urgent need to find pharmacological agents or vaccines. Although there are a lot of agents under investigation, there is no approved agent for the prevention or treatment of the COVID-19 yet. Treatment of patients remains mainly supportive as well as compassionate use of the agents under investigation. It is well established that excessive inflammatory and immune response as well as oxidative injury play a critical role in the pathogenesis of COVID-19. In this review, we aimed to update knowledge about pathogenesis, clinical features and pharmacological treatment of COVID-19 and review the potential beneficial effects of ancient antioxidant, anti-inflammatory and immunomodulatory molecule melatonin for prevention and treatment of COVID-19.

Title: Pathogenesis of virus-induced immune-mediated demyelination Content: Theiler's murine encephalomyelitis virus-induced demyelinating disease has been extensively studied as an attractive infectiousmodel for human multiple sclerosis. Virus-specific inflammatory Th1 cell responses followed by autoimmune responses to myelin antigens play a crucial role in the pathogenic processes leading to demyelination. Antibody and cytotoxic T cells (CTL) responses to virus appears to be primarily protective from demyelinating disease. Although the role of Th1 and CTL responses in the induction of demyelinating disease is controversial, assessment of cytokine sproduced locally in the central nervous system (CNS) during the course of disease and the effects of altered inflammatory cytokine levels strongly support the importance of Th1 responses in this virus-induced demyelinating disease. Induction of various chemokines and cytokines in different glial and antigen presenting cells upon viral infection appears to be an important initiation mechanism for inflammatory Th1 responses in the CNS. Coupled with the initial inflammatory responses, viral persistence in the CNS may be acritical factor for sustaining inflammatory responses and consequent immune-mediated demyelinating disease.

Title: The case of complement activation in COVID-19 multiorgan impact Content: The novel coronavirus disease COVID-19 originates in the lungs, but it may extend to other organs, causing, in severe cases, multiorgan damage, including cardiac injury and acute kidney injury. In severe cases, the presence of kidney injury is associated with increased risk of death, highlighting the relevance of this organ as a target of SARS-CoV-2 infection. COVID-19-associated tissue injury is not primarily mediated by viral infection, but rather is a result of the inflammatory host immune response, which drives hypercytokinemia and aggressive inflammation that affect lung parenchymal cells, diminishing oxygen uptake, but also endothelial cells, resulting in endotheliitis and thrombotic events and intravascular coagulation. The complement system represents the first response of the host immune system to SARS-CoV-2 infection, but there is growing evidence that unrestrained activation of complement induced by the virus in the lungs and other organs plays a major role in acute and chronic inflammation, endothelial cell dysfunction, thrombus formation, and intravascular coagulation, and ultimately contributes to multiple organ failure and death. In this review, we discuss the relative role of the different complement activation products in the pathogenesis of COVID-19-associated tissue inflammation and thrombosis and propose the hypothesis that blockade of the terminal complement pathway may represent a potential therapeutic option for the prevention and treatment of lung and multiorgan damage.

Title: The case of Complement activation in COVID-19 multiorgan impact Content: The novel coronavirus disease COVID-19 originates in the lungs, but may extend to other organs, causing, in severe cases, multiorgan damage, including cardiac injury and acute kidney injury. In severe cases, the presence of kidney injury is associated with increased risk of death, highlighting the relevance of this organ as a target of SARS-CoV-2 infection. COVID-19-associated tissue injury is not primarily mediated by viral infection, but rather is a result of the inflammatory host immune response, which drives hypercytokinemia and aggressive inflammation that affect lung parenchymal cells, diminishing oxygen uptake but also endothelial cells, resulting in endotheliitis and thrombotic events and intravascular coagulation. The complement system represents the first response of the host immune system to SARS-CoV-2 infection, but there is growing evidence that unrestrained activation of complement induced by the virus in the lungs and other organs plays a major role in acute and chronic inflammation, endothelial cell dysfunction, thrombus formation and intravascular coagulation, and ultimately contributes to multiple organ failure and death. In this review we will discuss the relative role of the different complement activation products in the pathogenesis of COVID-19-associated tissue inflammation and thrombosis and propose the hypothesis that blockade of the terminal complement pathway may represent a potential therapeutic option for the prevention and treatment of lung and multi-organ damage.

Title: Pulmonary Toxicity and Inflammatory Response of E-Cigarette Vape Cartridges Containing Medium-Chain Triglycerides Oil and Vitamin E Acetate: Implications in the Pathogenesis of EVALI. Content: Recently, there has been an outbreak associated with the use of e-cigarette or vaping products, associated lung injury (EVALI). The primary components of vaping products, vitamin E acetate (VEA) and medium-chain triglycerides (MCT), may be responsible for acute lung toxicity. Currently, little information is available on the physiological and biological effects of exposure to these products. We hypothesized that these e-cig vape cartridges and their constituents (VEA and MCT) induce pulmonary toxicity, mediated by oxidative damage and inflammatory responses, leading to acute lung injury. We studied the potential mechanisms of e-cig vape cartridge aerosol induced inflammatory response by evaluating the generation of reactive oxygen species by MCT, VEA, and cartridges and their effects on the inflammatory state of pulmonary epithelium and immune cells both in vitro and in vivo. Cells exposed to these aerosols generated reactive oxygen species, caused cytotoxicity, induced epithelial barrier dysfunction, and elicited an inflammatory response. Using a murine model, the parameters of acute toxicity to aerosol inhalation were assessed. Infiltration of neutrophils and lymphocytes was accompanied by significant increases in IL-6, eotaxin, and G-CSF in the bronchoalveolar lavage fluid (BALF). In mouse plasma, eicosanoid inflammatory mediators, leukotrienes, were significantly increased. Plasma from e-cig users also showed increased levels of hydroxyeicosatetraenoic acid (HETEs) and various eicosanoids. Exposure to e-cig vape cartridge aerosols showed the most significant effects and toxicity compared to MCT and VEA. In addition, we determined SARS-CoV-2 related proteins and found no impact associated with aerosol exposures from these tested cartridges. Overall, this study demonstrates acute exposure to specific e-cig vape cartridges induces in vitro cytotoxicity, barrier dysfunction, and inflammation and in vivo mouse exposure induces acute inflammation with elevated proinflammatory markers in the pathogenesis of EVALI.

Title: Attenuated interferon and pro-inflammatory response in SARS-CoV-2-infected human dendritic cells is associated with viral antagonism of STAT1 phosphorylation Content: Clinical manifestations of COVID-19 vary from asymptomatic virus shedding, non-specific pharyngitis, to pneumonia with silent hypoxia and respiratory failure. Dendritic cells and macrophages are sentinel cells for innate and adaptive immunity that affect the pathogenesis of SARS and MERS. However, the interplay between SARS-CoV-2 and these cell types remains unknown. Herein, we investigated the infection and host response of monocyte-derived dendritic cells (moDCs) and macrophages (MDMs) infected by SARS-CoV-2. We demonstrated that moDCs and MDMs were permissive to SARS-CoV-2 infection and protein expression but did not support productive virus replication. Importantly, SARS-CoV-2 launched an attenuated interferon response in both cell types. Additionally, SARS-CoV-2 triggered significant pro-inflammatory cytokine/chemokine expression in MDMs but not in moDCs. Further investigations suggested that this attenuated immune response to SARS-CoV-2 in moDCs was associated with viral antagonism of STAT1 phosphorylation. These findings on pathogenesis may explain the mild and insidious course of COVID-19 till late deterioration.

Title: Immunological and inflammatory profiles in mild and severe cases of COVID-19 Content: COVID-19 is associated with 5.1% mortality. Although the virological, epidemiological, clinical, and management outcome features of COVID-19 patients have been defined rapidly, the inflammatory and immune profiles require definition as they influence pathogenesis and clinical expression of COVID-19. Here we show lymphopenia, selective loss of CD4+ T cells, CD8+ T cells and NK cells, excessive T-cell activation and high expression of T-cell inhibitory molecules are more prominent in severe cases than in those with mild disease. CD8+ T cells in patients with severe disease express high levels of cytotoxic molecules. Histochemical studies of lung tissue from one fatality show sub-anatomical distributions of SARS-CoV-2 RNA and massive infiltration of T cells and macrophages. Thus, aberrant activation and dysregulation of CD8+ T cells occur in patients with severe COVID-19 disease, an effect that might be for pathogenesis of SARS-CoV-2 infection and indicate that immune-based targets for therapeutic interventions constitute a promising treatment for severe COVID-19 patients.

Title: Cytokine storm in COVID-19: pathogenesis and overview of anti-inflammatory agents used in treatment Content: COVID-19 infection has a heterogenous disease course; it may be asymptomatic or causes only mild symptoms in the majority of the cases, while immunologic complications such as macrophage activation syndrome also known as secondary hemophagocytic lymphohistiocytosis, resulting in cytokine storm syndrome and acute respiratory distress syndrome, may also occur in some patients. According to current literature, impairment of SARS-CoV-2 clearance due to genetic and viral features, lower levels of interferons, increased neutrophil extracellular traps, and increased pyroptosis and probable other unknown mechanisms create a background for severe disease course complicated by macrophage activation syndrome and cytokine storm. Various genetic mutations may also constitute a risk factor for severe disease course and occurrence of cytokine storm in COVID-19. Once, immunologic complications like cytokine storm occur, anti-viral treatment alone is not enough and should be combined with appropriate anti-inflammatory treatment. Anti-rheumatic drugs, which are tried for managing immunologic complications of COVID-19 infection, will also be discussed including chloroquine, hydroxychloroquine, JAK inhibitors, IL-6 inhibitors, IL-1 inhibitors, anti-TNF-α agents, corticosteroids, intravenous immunoglobulin (IVIG), and colchicine. Early recognition and appropriate treatment of immunologic complications will decrease the morbidity and mortality in COVID-19 infection, which requires the collaboration of infectious disease, lung, and intensive care unit specialists with other experts such as immunologists, rheumatologists, and hematologists.

Title: Insights into SARS-CoV-2 genome, structure, evolution, pathogenesis and therapies: Structural genomics approach Content: The sudden emergence of severe respiratory disease, caused by a novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has recently become a public health emergency. Genome sequence analysis of SARS-CoV-2 revealed its close resemblance to the earlier reported SARS-CoV and Middle East respiratory syndrome coronavirus (MERS-CoV). However, initial testing of the drugs used against SARS-CoV and MERS-CoV has been ineffective in controlling SARS-CoV-2. The present study highlights the genomic, proteomic, pathogenesis, and therapeutic strategies in SARS-CoV-2 infection. We have carried out sequence analysis of potential drug target proteins in SARS-CoV-2 and, compared them with SARS-CoV and MERS viruses. Analysis of mutations in the coding and non-coding regions, genetic diversity, and pathogenicity of SARS-CoV-2 has also been done. A detailed structural analysis of drug target proteins has been performed to gain insights into the mechanism of pathogenesis, structure-function relationships, and the development of structure-guided therapeutic approaches. The cytokine profiling and inflammatory signalling are different in the case of SARS-CoV-2 infection. We also highlighted possible therapies and their mechanism of action followed by clinical manifestation. Our analysis suggests a minimal variation in the genome sequence of SARS-CoV-2, may be responsible for a drastic change in the structures of target proteins, which makes available drugs ineffective.

Title: Insights into SARS-CoV-2 genome, structure, evolution, pathogenesis and therapies: Structural genomics approach Content: The sudden emergence of severe respiratory disease, caused by a novel severe acute respiratory syndrome coronavirus (SARS-CoV-2), has recently become a public health emergency. Genome sequence analysis of SARS-CoV-2 revealed its close resemblance to the earlier reported SARS-CoV and Middle East respiratory syndrome coronavirus (MERS-CoV). However, initial testing of the drugs used against SARS-CoV and MERS-CoV has been ineffective in controlling SARS-CoV-2. The present review looks to highlight the differences in genomic, proteomic, pathogenesis, and therapeutic strategies of SARS-CoV-2. We have carried out sequence analysis of potential drug target proteins in SARS-CoV-2 and, compared them with SARS-CoV-1 and MERS viruses. Analysis of mutations in the coding and non-coding regions, genetic diversity, and pathogenicity of SARS-CoV-2 has also been done. A detailed structural analysis of drug target proteins was performed to gain insights into the mechanism of pathogenesis, structure-function relationships, and the development of structure-guided therapeutic approaches. The cytokine profiling and inflammatory signalling are different in the case of SARS-CoV-2 infection. We also highlighted possible therapies and their mechanism of action followed by clinical manifestation. Our analysis suggests a minimal variation in the genome sequence of SARS-CoV-2, may be responsible for a drastic change in the structures of target proteins, makes available drugs ineffective.

Title: Coronavirus Interferon Antagonists Differentially Modulate the Host Response during Replication in Macrophages Content: Coronaviruses encode multiple interferon antagonists that modulate the host response to virus replication. Here, we evaluated pathogenesis and host transcription in response to infection with murine coronaviruses encoding independent mutations in two different viral antagonists: the deubiquitinase (DUB) within nonstructural protein 3 and the endoribonuclease (EndoU) within nonstructural protein 15. The virus with reduced ability to deubiquitinate proteins, herein termed the DUBmut virus, was engineered via X-ray structure-guided mutagenesis and activates an earlier interferon response than the wild type virus. However, the replication kinetics of DUBmut in cultured cells are similar to wild type virus and pathogenesis in mice is also similar to what was observed during infection with wild type virus. On the other hand, we previously reported that an EndoUmut virus containing an inactivated endoribonuclease activity elicited rapid and robust activation of type I interferon, which limited virus replication and pathogenesis. Here, using a transcriptomics approach, we compared the scope and kinetics of the host response to the wild type, DUBmut, and EndoUmut viruses in infected macrophages. We found that the EndoUmut virus activates a focused response, predominantly involving type I interferons and a subset of interferon-responsive genes, within 12 hours after infection. In contrast, the wild type and DUBmut viruses stimulate upregulation of over 2,800 genes, including activation of unfolded protein response (UPR) pathways and a proinflammatory profile associated with viral pathogenesis. This study highlights the role of viral interferon antagonists in shaping the kinetics and magnitude of the host response during virus infection and demonstrates that inactivation of a dominant viral antagonist, the coronavirus endoribonuclease, dramatically alters the host response in macrophages and the disease process. Author Summary Macrophages are an important cell type during coronavirus infections because they “notice” the infection and respond by activating type I interferons, which then act to establish antiviral defenses and limit virus replication. In turn, coronaviruses encode proteins that mitigate the cell’s ability to detect virus replication or amplify the interferon response. Here, we evaluated the host macrophage response to two independent mutant coronaviruses: one with a reduced deubiquitinating activity (DUBmut), and the other containing an inactivated endoribonuclease (EndoUmut). We observed a rapid, robust, and focused response to the EndoUmut virus, which was characterized by enhanced expression of interferon and interferon-stimulated genes. These results indicate that coronaviruses utilize EndoU activity for preventing early activation of interferon in macrophages, thereby allowing for viral replication. In contrast, DUBmut elicited a transient interferon response and ultimately activated over 2,800 genes, including many well-known players in pro-inflammatory pathways and the unfolded protein response. These DUBmut-induced pathways are associated with development and progression of significant disease, similar to what is observed during wild type virus infection. This study demonstrates the distinct consequences of mutating different viral interferon antagonists and reveals that intact coronaviral EndoU activity substantially contributes to the ability of coronaviruses to replicate in macrophages.

Title: Eosinophil Response Against Classical and Emerging Respiratory Viruses: COVID-19. Content: Eosinophils were discovered more than 140 years ago. This polymorphonuclear leukocyte has a very active metabolism, containing numerous intracellular secretory granules that allow it exerts multiple functions in both health and disease status. Classically, eosinophils have been considered as important immune cells in the pathogenesis of inflammatory processes such as parasitic helminth infections and allergic or pulmonary diseases like asthma, being always associated to a type 2 immune response; furthermore, in the last years, it has been linked to immune response conferring host protection against fungi, bacteria, and viruses, recognizing them through several molecules such as toll-like receptors (TLRs) or retinoic acid-inducible gene 1 (RIG-1)-like receptor (RLR). The immune protection is exerted through multiple mechanisms and properties of these cells. They contain numerous cytoplasmatic granules that release cationic proteins, cytokines, chemokines and other molecules that contribute to their functions. In addition to their competence as effectors cells, its capabilities like antigen-presenting cell allow them to act in multiple situations promoting diverse aspects of the immune response. This review summarizes diverse aspects of eosinophil biology and mainly, it goes over the mechanisms and roles carried out by eosinophils in host defence against virus infections and vaccines response, focusing the attention in respiratory viruses like the new coronavirus, SARS-CoV-2.

Title: Eosinophil Response Against Classical and Emerging Respiratory Viruses: COVID-19 Content: Eosinophils were discovered more than 140 years ago. This polymorphonuclear leukocyte has a very active metabolism, containing numerous intracellular secretory granules that allow it exerts multiple functions in both health and disease status. Classically, eosinophils have been considered as important immune cells in the pathogenesis of inflammatory processes such as parasitic helminth infections and allergic or pulmonary diseases like asthma, being always associated to a type 2 immune response; furthermore, in the last years, it has been linked to immune response conferring host protection against fungi, bacteria, and viruses, recognizing them through several molecules such as toll-like receptors (TLRs) or retinoic acid-inducible gene 1 (RIG-1)-like receptor (RLR). The immune protection is exerted through multiple mechanisms and properties of these cells. They contain numerous cytoplasmatic granules that release cationic proteins, cytokines, chemokines and other molecules that contribute to their functions. In addition to their competence as effectors cells, its capabilities like antigen-presenting cell allow them to act in multiple situations promoting diverse aspects of the immune response. This review summarizes diverse aspects of eosinophil biology and mainly, it goes over the mechanisms and roles carried out by eosinophils in host defence against virus infections and vaccines response, focusing the attention in respiratory viruses like the new coronavirus, SARS-CoV-2.

Title: Immunopathology of highly virulent pathogens: insights from Ebola virus Content: Ebola virus is a highly virulent pathogen capable of inducing a frequently lethal hemorrhagic fever syndrome. Accumulating evidence indicates that the virus actively subverts both innate and adaptive immune responses and triggers harmful inflammatory responses as it inflicts direct tissue damage. The host immune system is ultimately overwhelmed by a combination of inflammatory factors and virus-induced cell damage, particularly in the liver and vasculature, often leading to death from septic shock. We summarize the mechanisms of immune dysregulation and virus-mediated cell damage in Ebola virus–infected patients. Future approaches to prevention and treatment of infection will be guided by answers to unresolved questions about interspecies transmission, molecular mechanisms of pathogenesis, and protective adaptive and innate immune responses to Ebola virus.

Title: Elevated serum levels of decoy receptor 3 are associated with disease severity in patients with hemorrhagic fever with renal syndrome Content: Hemorrhagic fever with renal syndrome (HFRS) is an acute viral infectious disease characterized by fever, hemorrhage and renal failure. HFRS has become a serious public health problem in China. Unfortunately, the pathogenesis of HFRS has not been completely clarified. The aim of this study is to investigate the changes of decoy receptor 3 (DcR3) and to further explore its potential roles in HFRS. The levels of serum DcR3 were measured by sandwich ELISA. We found serum DcR3 levels increased significantly, which reached peak value during the oliguric phase and in the critical group. Moreover, serum DcR3 levels were closely related to the levels of pro-inflammatory cytokines tumor necrosis factor-α (TNF-α) and parameters reflecting kidney injury including BUN, creatinine (Cr) and proteinuria. This study indicates that high levels of serum DcR3 have associations with the disease stages, severity and degree of kidney damage. Meanwhile, our results suggest that DcR3 may play a dual role in HFRS pathogenesis. First, DcR3 is involved in the inflammatory cascade response resulting in capillary permeability and kidney injury in the early stage. Secondly, HTNV infection induced DcR3 expression at the convalescent phase may act as a feed-back mechanism in anti-inflammatory response. Thus, a study of DcR3 is essential for a better understanding of HFRS pathogenesis.

Title: Expression of inflammation-related genes in the lung of BALB/c mice response to H7N9 influenza A virus with different pathogenicity Content: H7N9 influenza A virus (IAV)-infected human cases are increasing and reported over 200 mortalities since its first emergence in 2013. Host inflammatory response contributes to the clearance of influenza virus; meanwhile, the induced “cytokine storm” also leads to pathological lesions. However, what inflammation-related response of the host for H7N9 influenza A virus infection to survival from injures of exuberant cytokine release is still obscure. In this research, expression pattern and histological distribution of inflammation-related genes, RIP3, NLRP3, IL-1β, TNF-α, Slit2 and Robo4 in the lung of BALB/c mice infected with two H7N9 IAV strains with only a PB2 residue 627 difference were investigated, as well as the histopathological injury of the lung. Results showed that significantly higher expression level of NLRP3, RIP3, IL-1β and TNF-α in H7N9-infected groups compared with the control would play a key role in driving lung pathological lesion. While the expression level of Slit2 and Robo4 in H7N9 rV(K627E) group had significantly increased trend than V(K627) which might be the main factor to inhibit the interstitial pneumonia and infiltration. Also, H7N9 induced the histopathological changes in the lung of infected mice, and RIP3, NLRP3, IL-1β, TNF-α, Slit2 and Robo4 showed cell-specific distribution in the lung. The results will provide basic data for further research on the mechanism of inflammatory response and understanding of the role of site 627 in PB2 in H7N9 IAVs infection. In addition, enhancing the resilience of the host vascular system to the inflammatory response by regulation of Slit2–Robo4 signaling pathway might provide a novel strategy for H7N9 IAVs infection.

Title: Pathogenic T cells and inflammatory monocytes incite inflammatory storm in severe COVID-19 patients Content: Pathogenic human coronavirus infections, such as severe acute respiratory syndrome CoV (SARS-CoV) and Middle East respiratory syndrome CoV (MERS-CoV), cause high morbidity and mortality1, 2 Recently, a severe pneumonia-associated respiratory syndrome caused by a new coronavirus (SARS-CoV-2) was reported at December 2019 in the city Wuhan, Hubei province, China3, 4, 5, which was also named as pneumonia-associated respiratory syndrome (PARS)6 and can cause coronavirus disease 2019 (COVID-19) to seriously endanger human health Up to 24th of February 2020, at least 77779 cases have been reported with 2666 fatal cases according to the report from China CDC However, the immune mechanism that potential orchestrated acute mortality from COVID-19 patients is still unknown Here we show that after the SARS-CoV-2 infection, CD4+ T lymphocytes are rapidly activated to become pathogenic T helper (Th) 1 cells and generate GM-CSF etc The cytokines environment induces inflammatory CD14+CD16+ monocytes with high expression of IL-6 and accelerate the inflammation Given that large amount of inflammatory cells infiltrations have been observed in lungs from severe COVID-19 patients7, 8, these aberrant pathogenic Th1 cells and inflammatory monocytes may enter the pulmonary circulation in huge numbers and play an immune damaging role to causing lung functional disability and quick mortality Our results demonstrate that excessive non-effective host immune responses by pathogenic T cells and inflammatory monocytes may associate with severe lung pathology Thus, we suggest that monoclonal antibodies targeting GM-CSF or interleukin 6 may be effective in blocking inflammatory storms and, therefore, be a promising treatment of severe COVID-19 patients

Title: Transcriptomic characteristics of bronchoalveolar lavage fluid and peripheral blood mononuclear cells in COVID-19 patients Content: Circulating in China and 158 other countries and areas, the ongoing COVID-19 outbreak has caused devastating mortality and posed a great threat to public health. However, efforts to identify effectively supportive therapeutic drugs and treatments has been hampered by our limited understanding of host immune response for this fatal disease. To characterize the transcriptional signatures of host inflammatory response to SARS-CoV-2 (HCoV-19) infection, we carried out transcriptome sequencing of the RNAs isolated from the bronchoalveolar lavage fluid (BALF) and peripheral blood mononuclear cells (PBMC) specimens of COVID-19 patients. Our results reveal distinct host inflammatory cytokine profiles to SARS-CoV-2 infection in patients, and highlight the association between COVID-19 pathogenesis and excessive cytokine release such as CCL2/MCP-1, CXCL10/IP-10, CCL3/MIP-1A, and CCL4/MIP1B. Furthermore, SARS-CoV-2 induced activation of apoptosis and P53 signalling pathway in lymphocytes may be the cause of patients’ lymphopenia. The transcriptome dataset of COVID-19 patients would be a valuable resource for clinical guidance on anti-inflammatory medication and understanding the molecular mechansims of host response.

Title: Transcriptomic characteristics of bronchoalveolar lavage fluid and peripheral blood mononuclear cells in COVID-19 patients Content: Circulating in China and 158 other countries and areas, the ongoing COVID-19 outbreak has caused devastating mortality and posed a great threat to public health. However, efforts to identify effectively supportive therapeutic drugs and treatments has been hampered by our limited understanding of host immune response for this fatal disease. To characterize the transcriptional signatures of host inflammatory response to SARS-CoV-2 (HCoV-19) infection, we carried out transcriptome sequencing of the RNAs isolated from the bronchoalveolar lavage fluid (BALF) and peripheral blood mononuclear cells (PBMC) specimens of COVID-19 patients. Our results reveal distinct host inflammatory cytokine profiles to SARS-CoV-2 infection in patients, and highlight the association between COVID-19 pathogenesis and excessive cytokine release such as CCL2/MCP-1, CXCL10/IP-10, CCL3/MIP-1A, and CCL4/MIP1B. Furthermore, SARS-CoV-2 induced activation of apoptosis and P53 signalling pathway in lymphocytes may be the cause of patients' lymphopenia. The transcriptome dataset of COVID-19 patients would be a valuable resource for clinical guidance on anti-inflammatory medication and understanding the molecular mechansims of host response.

Title: Inflammatory responses relate to distinct bronchoalveolar lavage lipidome in community-acquired pneumonia patients: a pilot study Content: BACKGROUND: Community-acquired pneumonia (CAP) is a leading cause of morbidity and mortality worldwide. Antibiotics are losing their effectiveness due to the emerging infectious diseases, the scarcity of novel antibiotics, and the contributions of antibiotic misuse and overuse to resistance. Characterization of the lipidomic response to pneumonia and exploring the “lipidomic phenotype” can provide new insight into the underlying mechanisms of pathogenesis and potential avenues for diagnostic and therapeutic treatments. METHODS: Lipid profiles of bronchoalveolar lavage fluid (BALF) samples were generated through untargeted lipidomic profiling analysis using high-performance liquid chromatography with mass spectrometry (HPLC-MS). Principal component analysis (PCA) was applied to identify possible sources of variations among samples. Partitioning clustering analysis (k-means) was employed to evaluate the existence of distinct lipidomic clusters. RESULTS: PCA showed that BALF lipidomes differed significantly between CAP (n = 52) and controls (n = 68, including 35 healthy volunteers and 33 patients with non-infectious lung diseases); while no clear separation was found between severe CAP and non-severe CAP cases. Lactosylceramides were the most prominently elevated lipid constituent in CAP. Clustering analysis revealed three separate lipid profiles; subjects in each cluster exhibited significant differences in disease severity, incidence of hypoxemia, percentages of phagocytes in BALF, and serum concentrations of albumin and total cholesterol (all p < 0.05). In addition, SM (d34:1) was negatively related to macrophage (adjusted r = − 0.462, p < 0.0001) and PE (18:1p/20:4) was positively correlated with polymorphonuclear neutrophil (PMN) percentages of BALF (adjusted r = 0.541, p < 0.0001). The 30-day mortality did not differ amongst three clusters (p < 0.05). CONCLUSIONS: Our data suggest that specific lower airway lipid composition is related to different intensities of host inflammatory responses, and may contribute to functionally relevant shifts in disease pathogenesis in CAP individuals. These findings argue for the need to tailor therapy based on specific lipid profiles and related inflammatory status. TRIAL REGISTRATION: ClinicalTrials.gov (NCT03093220). Registered on 28 March 2017 (retrospectively registered). ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s12931-019-1028-8) contains supplementary material, which is available to authorized users.

Title: Harnessing resolving‐based therapeutics to treat pulmonary viral infections: What can the future offer to COVID‐19? Content: Inflammation is generally believed to be a protective response in the context of infectious diseases. However, altered inflammatory responses can contribute to disease in infected individuals. Multiple mediators that drive the resolution of inflammation have been described. Overall, mediators of resolution tend to decrease inflammatory responses and provide normal or greater ability of the host to deal with infection. In the lung, it seems that pro‐resolving molecules or strategies that promote their increase tend to decrease inflammation and lung injury and facilitate control of bacterial or viral burden. Here, we argue that the demonstrated anti‐inflammatory, pro‐resolving, anti‐thrombogenic and anti‐microbial effects of pro‐resolution mediators may be useful in the treatment of the late stages of disease in patients with COVID‐19.

Title: Harnessing inflammation resolving-based therapeutic agents to treat pulmonary viral infections: What can the future offer to COVID-19? Content: Inflammation is generally accepted as a component of the host defence system and a protective response in the context of infectious diseases. However, altered inflammatory responses can contribute to disease in infected individuals. Many endogenous mediators that drive the resolution of inflammation are now known. Overall, mediators of resolution tend to decrease inflammatory responses and provide normal or greater ability of the host to deal with infection. In the lung, it seems that pro-resolution molecules, or strategies that promote their increase, tend to suppress inflammation and lung injury and facilitate control of bacterial or viral burden. Here, we argue that the demonstrated anti-inflammatory, pro-resolving, anti-thrombogenic and anti-microbial effects of such endogenous mediators of resolution may be useful in the treatment of the late stages of the disease in patients with COVID-19.

Title: Microglia Are Essential to Protective Antiviral Immunity: Lessons From Mouse Models of Viral Encephalitis Content: Viral encephalitis is a rare but clinically serious consequence of viral invasion of the brain and insight into its pathogenesis is urgently needed. Important research questions concern the involvement of the host innate immune response in pathogenesis, key to which is the role played by microglia, resident macrophages of the brain parenchyma. Do microglia have a protective function, by coordinating the innate immune response to viral infection, or do they drive pathogenic neuroinflammation? Here we synthesize recent data from mouse models of acute viral encephalitis, which reveal an unambiguously protective role for microglia. Depletion of microglia, via blockade of colony-stimulating factor 1 receptor (CSF1R) signaling, led to increased viral replication accompanied by more severe neurological disease and heightened mortality. Whilst the underlying mechanism(s) remain to be defined, microglial interactions with T cells and phagocytosis of infected neurones appear to play a role. Paradoxically, the production of inflammatory cytokines was increased in several instances following viral infection in microglia-depleted brains, suggesting that: (i) cells other than microglia mediate inflammatory responses and/or (ii) microglia may exert a regulatory function. Under certain circumstances the microglial antiviral response might contribute negatively to longer-term neurological sequelae, although fewer studies have focused on this aspect in encephalitis models. Understanding regulation of the microglial response, and how it contributes to disease is therefore a priority for future studies. Collectively, these findings demonstrate the central role of microglia in pathogenesis, suggesting the exciting possibility that defects of microglial function might contribute to encephalitis susceptibility and/or outcome in humans.

Title: COVID 19 and heart failure: from infection to inflammation and angiotensin II stimulation. Searching for evidence from a new disease Content: Patients with cardiovascular disease and, namely, heart failure are more susceptible to coronavirus disease 2019 (COVID‐19) and have a more severe clinical course once infected. Heart failure and myocardial damage, shown by increased troponin plasma levels, occur in at least 10% of patients hospitalized for COVID‐19 with higher percentages, 25%–35% or more, when patients critically ill or with concomitant cardiac disease are considered. Myocardial injury may be elicited by multiple mechanisms, including those occurring with all severe infections, such as fever, tachycardia, adrenergic stimulation, as well as those caused by the exaggerated inflammatory response, endotheliitis and, in some cases, myocarditis that have been shown in patients with COVID‐19. A key role may be that of the renin–angiotensin‐aldosterone system. Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) infects human cells binding to angiotensin‐converting‐enzyme 2 (ACE2), an enzyme responsible of the cleavage of angiotensin II into angiotensin 1–7, which has vasodilating and anti‐inflammatory effects. Virus‐mediated downregulation of ACE2 may increase angiotensin II stimulation and contribute to the deleterious hyper‐inflammatory reaction of COVID‐19. On the other hand, ACE2 may be upregulated in patients with cardiac disease and treated with ACE inhibitors or angiotensin receptor blockers. ACE2 upregulation may increase the susceptibility to COVID‐19 but may be also protective versus angiotensin II mediated vasoconstriction and inflammatory activation. Recent data show the lack of untoward effects of ACE inhibitors or angiotensin receptor blockers for COVID‐19 infection and severity. Prospective trials are needed to ascertain whether these drugs may have protective effects. This article is protected by copyright. All rights reserved.

Title: COVID-19 and heart failure: from infection to inflammation and angiotensin II stimulation. Searching for evidence from a new disease Content: Patients with cardiovascular disease and, namely, heart failure are more susceptible to coronavirus disease 2019 (COVID-19) and have a more severe clinical course once infected. Heart failure and myocardial damage, shown by increased troponin plasma levels, occur in at least 10% of patients hospitalized for COVID-19 with higher percentages, 25% to 35% or more, when patients critically ill or with concomitant cardiac disease are considered. Myocardial injury may be elicited by multiple mechanisms, including those occurring with all severe infections, such as fever, tachycardia, adrenergic stimulation, as well as those caused by an exaggerated inflammatory response, endotheliitis and, in some cases, myocarditis that have been shown in patients with COVID-19. A key role may be that of the renin-angiotensin-aldosterone system. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infects human cells binding to angiotensin-converting enzyme 2 (ACE2), an enzyme responsible for the cleavage of angiotensin II into angiotensin 1-7, which has vasodilating and anti-inflammatory effects. Virus-mediated down-regulation of ACE2 may increase angiotensin II stimulation and contribute to the deleterious hyper-inflammatory reaction of COVID-19. On the other hand, ACE2 may be up-regulated in patients with cardiac disease and treated with ACE inhibitors or angiotensin receptor blockers. ACE2 up-regulation may increase the susceptibility to COVID-19 but may be also protective vs. angiotensin II-mediated vasoconstriction and inflammatory activation. Recent data show the lack of untoward effects of ACE inhibitors or angiotensin receptor blockers for COVID-19 infection and severity. Prospective trials are needed to ascertain whether these drugs may have protective effects.

Title: Neuropilin-1 modulates interferon-γ-stimulated signaling in brain microvascular endothelial cells. Content: Inflammatory response of blood-brain barrier (BBB) endothelial cells plays an important role in pathogenesis of many central nervous system inflammatory diseases, including multiple sclerosis; however, the molecular mechanism mediating BBB endothelial cell inflammatory response remains unclear. In this study, we first observed that knockdown of neuropilin-1 (NRP1), a co-receptor of several structurally diverse ligands, suppressed interferon-γ (IFNγ)-induced C-X-C motif chemokine 10 expression and activation of STAT1 in brain microvascular endothelial cells in a Rac1-dependent manner. Moreover, endothelial-specific NRP1-knockout mice, VECadherin-Cre-ERT2/NRP1flox/flox mice, showed attenuated disease progression during experimental autoimmune encephalomyelitis, a mouse neuroinflammatory disease model. Detailed analysis utilizing histological staining, quantitative PCR, flow cytometry and magnetic resonance imaging demonstrated that deletion of endothelial NRP1 suppressed neuron demyelination, altered lymphocyte infiltration, preserved BBB function and decreased activation of the STAT1-CXCL10 pathway. Furthermore, increased expression of NRP1 was observed in endothelial cells of acute multiple sclerosis lesions. Our data identify a new molecular mechanism of brain microvascular endothelial inflammatory response through NRP1-IFNγ crosstalk that could be a potential target for intervention of endothelial cell dysfunction in neuroinflammatory diseases.

Title: Differential diagnosis and clinical management of a case of COVID-19 in a stage III lung cancer patient treated with radio-chemotherapy and durvalumab. Content: BACKGROUND: pneumonitis is common in NSCLC and can be a consequence of the disease itself, super-infection, or side effects of the treatment. Recently Covid-19 added to the list of possible causes, emerging as a concrete threat for already frail patients. CASE REPORT: a 75-years-old stage-III NSCLC patient underwent radical radio-chemotherapy followed by consolidation durvalumab at our Institution. After four cycles, immunotherapy was suspended due to symptomatic pneumonitis responsive to oral steroids. Nevertheless, he suddenly developed fever and severe dyspnea. Chest radiography described diffuse alveolar and interstitial infiltrates and RT-PCR confirmed the diagnosis of Covid-19. His clinical conditions worsened despite antiviral therapy and supplemental oxygen and the patient died three days after admission. DISCUSSION: this paper highlights the remarkable clinical and radiological similarity of pneumonitis causated by Covid-19 and immunotherapy, hampering differential diagnosis and corroborating the hypothesis that inflammatory molecules, and possibly PD-L1, play a central role in Covid-19 pathogenesis.

Title: COVID-19 and Liver Dysfunction: Current Insights and Emergent Therapeutic Strategies Content: The outbreak of coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has attracted increasing worldwide attention. Cases of liver damage or dysfunction (mainly characterized by moderately elevated serum aspartate aminotransferase levels) have been reported among patients with COVID-19. However, it is currently uncertain whether the COVID-19-related liver damage/dysfunction is due mainly to the viral infection per se or other coexisting conditions, such as the use of potentially hepatotoxic drugs and the coexistence of systemic inflammatory response, respiratory distress syndrome-induced hypoxia, and multiple organ dysfunction. Based on the current evidence from case reports and case series, this review article focuses on the demographic and clinical characteristics, potential mechanisms, and treatment options for COVID-19-related liver dysfunction. This review also describes the geographical and demographic distribution of COVID-19-related liver dysfunction, as well as possible underlying mechanisms linking COVID-19 to liver dysfunction, in order to facilitate future drug development, prevention, and control measures for COVID-19.

Title: Transcriptomic profiling of disease severity in patients with COVID-19 reveals role of blood clotting and vasculature related genes Content: COVID-19 caused by SARS-CoV-2 manifests as a range of symptoms. Understanding the molecular mechanisms responsible for immuno-pathogenesis of disease is important for treatment and management of COVID-19. We examined host transcriptomes in moderate and severe COVID-19 cases with a view to identifying pathways that affect its progression. RNA extracted from whole blood of COVID-19 cases was analysed by microarray analysis. Moderate and severe cases were compared with healthy controls and differentially regulated genes (DEGs) categorized into cellular pathways. DEGs in COVID-19 cases were mostly related to host immune activation and cytokine signaling, pathogen uptake, host defenses, blood and vasculature genes, and SARS-CoV-2- and other virus- affected pathways. The DEGs in these pathways were increased in severe compared with moderate cases. In a severe COVID-19 patient with an unfavourable outcome we observed dysregulation of genes in platelet homeostasis and cardiac conduction and fibrin clotting with disease progression.

Title: Interferon and cytokine responses to Crimean Congo hemorrhagic fever virus; an emerging and neglected viral zonoosis Content: Abstract Crimean Congo hemorrhagic fever virus (CCHFV) causes an acute disease with the potential of a fatal outcome. The virus is prevalent in about 30 countries. Clinical symptoms of infection commonly include fever, myalgia, and hemorrhages. Levels of liver enzymes are raised, and bleeding markers are often increased. A role of inflammatory cytokines in the pathogenesis has been suggested, and CCHFV employs a range of passive and active mechanisms to avoid induction of the antiviral type I interferons. Here, we review the most recent findings on the molecular pathogenesis and the interaction of CCHFV with the type I interferon and cytokine responses and discuss implications for pathogenesis.

Title: Recommendations for coronavirus infection in rheumatic diseases treated with biologic therapy Content: The Coronavirus-associated disease, that was first identified in 2019 in China (CoViD-19), is a pandemic caused by a bat-derived beta-coronavirus, named SARS-CoV2. It shares homology with SARS and MERS-CoV, responsible for past outbreaks in China and in Middle East. SARS-CoV2 spread from China where the first infections were described in December 2019 and is responsible for the respiratory symptoms that can lead to acute respiratory distress syndrome. A cytokine storm has been shown in patients who develop fatal complications, as observed in past coronavirus infections. The management includes ventilatory support and broad-spectrum antiviral drugs, empirically utilized, as a targeted therapy and vaccines have not been developed. Based upon our limited knowledge on the pathogenesis of CoViD-19, a potential role of some anti-rheumatic drugs may be hypothesized, acting as direct antivirals or targeting host immune response. Antimalarial drugs, commonly used in rheumatology, may alter the lysosomal proteases that mediates the viral entry into the cell and have demonstrated efficacy in improving the infection. Anti-IL-1 and anti-IL-6 may interfere with the cytokine storm in severe cases and use of tocilizumab has shown good outcomes in a small cohort. Baricitinib has both antiviral and anti-inflammatory properties. Checkpoints inhibitors such as anti-CD200 and anti-PD1 could have a role in the treatment of CoViD-19. Rheumatic disease patients taking immunosuppressive drugs should be recommended to maintain the chronic therapy, prevent infection by avoiding social contacts and pausing immunosuppressants in case of infection. National and international registries are being created to collect data on rheumatic patients with CoViD-19.

Title: COVID-19 severity correlates with airway epithelium-immune cell interactions identified by single-cell analysis. Content: To investigate the immune response and mechanisms associated with severe coronavirus disease 2019 (COVID-19), we performed single-cell RNA sequencing on nasopharyngeal and bronchial samples from 19 clinically well-characterized patients with moderate or critical disease and from five healthy controls. We identified airway epithelial cell types and states vulnerable to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. In patients with COVID-19, epithelial cells showed an average three-fold increase in expression of the SARS-CoV-2 entry receptor ACE2, which correlated with interferon signals by immune cells. Compared to moderate cases, critical cases exhibited stronger interactions between epithelial and immune cells, as indicated by ligand-receptor expression profiles, and activated immune cells, including inflammatory macrophages expressing CCL2, CCL3, CCL20, CXCL1, CXCL3, CXCL10, IL8, IL1B and TNF. The transcriptional differences in critical cases compared to moderate cases likely contribute to clinical observations of heightened inflammatory tissue damage, lung injury and respiratory failure. Our data suggest that pharmacologic inhibition of the CCR1 and/or CCR5 pathways might suppress immune hyperactivation in critical COVID-19.

Title: COVID-19 severity correlates with airway epithelium-immune cell interactions identified by single-cell analysis Content: To investigate the immune response and mechanisms associated with severe coronavirus disease 2019 (COVID-19), we performed single-cell RNA sequencing on nasopharyngeal and bronchial samples from 19 clinically well-characterized patients with moderate or critical disease and from five healthy controls. We identified airway epithelial cell types and states vulnerable to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. In patients with COVID-19, epithelial cells showed an average three-fold increase in expression of the SARS-CoV-2 entry receptor ACE2, which correlated with interferon signals by immune cells. Compared to moderate cases, critical cases exhibited stronger interactions between epithelial and immune cells, as indicated by ligand-receptor expression profiles, and activated immune cells, including inflammatory macrophages expressing CCL2, CCL3, CCL20, CXCL1, CXCL3, CXCL10, IL8, IL1B and TNF. The transcriptional differences in critical cases compared to moderate cases likely contribute to clinical observations of heightened inflammatory tissue damage, lung injury and respiratory failure. Our data suggest that pharmacologic inhibition of the CCR1 and/or CCR5 pathways might suppress immune hyperactivation in critical COVID-19.

Title: Contribution of Fcγ Receptor-Mediated Immunity to the Pathogenesis Caused by the Human Respiratory Syncytial Virus Content: The human Respiratory Syncytial Virus (hRSV) is the leading cause of severe acute lower respiratory tract infections (ALRTIs) in humans at all ages and is the main cause of hospitalization due to pneumonia, asthma, and bronchiolitis in infants. hRSV symptoms mainly develop due to an excessive host immune and inflammatory response in the respiratory tissue. hRSV infection during life is frequent and likely because of non-optimal immunological memory is developed against this virus. Vaccine development against this pathogen has been delayed after the detrimental effects produced in children by vaccination with a formalin-inactivated hRSV preparation (FI-hRSV), which caused enhanced disease upon natural viral infection. Since then, several studies have focused on understanding the mechanisms underlying such disease exacerbation. Along these lines, several studies have suggested that antibodies elicited by immunization with FI-hRSV show low neutralizing capacity and promote the formation of immune complexes containing hRSV (hRSV-ICs), which contribute to hRSV pathogenesis through the engagement of Fc gamma receptors (FcγRs) expressed on the surface of immune cells. Furthermore, a role for FcγRs is supported by studies evaluating the contribution of these molecules to hRSV-induced disease. These studies have shown that FcγRs can modulate viral clearance by the host and the inflammatory response triggered by hRSV infection. In addition, ICs can facilitate viral entry into host cells expressing FcγRs, thus extending hRSV infectivity. In this article, we discuss current knowledge relative to the contribution of hRSV-ICs and FcγRs to the pathogenesis caused by hRSV and their putative role in the exacerbation of the disease caused by this virus after FI-hRSV vaccination. A better understanding FcγRs involvement in the immune response against hRSV will contribute to the development of new prophylactic or therapeutic tools to promote virus clearance with limited inflammatory damage to the airways.

Title: Cancer Patients Have a Higher Risk Regarding COVID-19 - and Vice Versa? Content: The world is currently suffering from a pandemic which has claimed the lives of over 230,000 people to date The responsible virus is called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and causes the coronavirus disease 2019 (COVID-19), which is mainly characterized by fever, cough and shortness of breath In severe cases, the disease can lead to respiratory distress syndrome and septic shock, which are mostly fatal for the patient The severity of disease progression was hypothesized to be related to an overshooting immune response and was correlated with age and comorbidities, including cancer A lot of research has lately been focused on the pathogenesis and acute consequences of COVID-19 However, the possibility of long-term consequences caused by viral infections which has been shown for other viruses are not to be neglected In this regard, this opinion discusses the interplay of SARS-CoV-2 infection and cancer with special focus on the inflammatory immune response and tissue damage caused by infection We summarize the available literature on COVID-19 suggesting an increased risk for severe disease progression in cancer patients, and we discuss the possibility that SARS-CoV-2 could contribute to cancer development We offer lines of thought to provide ideas for urgently needed studies on the potential long-term effects of SARS-CoV-2 infection