bluuebunny/crossref_metadata_2025_split huggingface dataset:
Complement C3 increases cardiomyocyte resistance to apoptosis in response to hypoxia
Authors: Fang Zhou , Li Xiang , Xu Fou , Elvington Michelle , Kulkarni Hrishikesh , Atkinson John P. , Zhang Ming 
Published: January 2023

Abstract
Hypoxia takes places in pathogenic conditions, such as heart ischemia. Complements factors have been reported to play an important role in ischemia-reperfusion injury in various animal models. We studied the cellular response to complement under hypoxia condition using a human cardiomyocyte cell line AC16. Under hypoxia condition without serum (thus no exogenous complements provided), these cardiomyocytes underwent apoptosis. However, when pure human C3 was supplemented after hypoxia, these cells had less apoptosis and maintained a reasonable survival rate. The results indicate that complement C3 can increase the cardiomyocytes resistance to apoptosis under the hypoxia condition.
The Functional Role of CD169+ Macrophages in Septic Shock
Authors: Yeung Stephen T , Khanna Kamal Mohan 
Published: January 2023

Abstract
Sepsis affects more than 30 million people and accounts for approximately 6 million deaths worldwide each year. Sepsis is often associated with gram-positive, gram-negative, or fungal infections. Currently, there are no known cures for sepsis; however, current therapeutic strategies consist of supportive care to keep vital organs functional and antibiotics to combat infections, with survival prognosis contingent on early detection. Our current knowledge of the cellular and molecular mechanisms that regulate the inflammatory pathways resulting in sepsis is limited. Notably, we know little about the precise subpopulations of immune cells that play a central role during sepsis. Here we examined the specific role of CD169+ macrophages and its immunological receptors in septic shock. We utilized the CD169-DTR mouse to selectively and temporally deplete CD169+ macrophages. Using this model, we examined survival, cytokine/chemokine milieu, and cellularity in response to gram-negative LPS. We report the critical role of CD169+ macrophages and the CD169 receptor in protection against LPS induced septic shock. We show that in the absence of these macrophages, mice stimulated with sublethal LPS fail to survive and exhibit increased inflammatory cytokines and impaired IL-10 production. Protection against LPS induced lethality is rescued by supplemental treatment with recombinant IL-10. Lastly, we show that following LPS treatment, CD169+ macrophages are the initial targeted cell. These findings not only reveal a pivotal role for CD169+ macrophages but also the role for the CD169 receptor as a critical mediator of protection from sepsis induced lethality, and provide new therapeutic targets against sepsis.
Neutrophils are more effective than monocytes at containment and killing of Listeria monocytogenes
Authors: Okunnu Busola , Berg Rance E 
Published: January 2023

Abstract
Neutrophils and monocytes have previously been shown to be important for host protection during infection with Listeria monocytogenes (Lm). Previous studies have shown that simultaneous depletion of neutrophils and monocytes with the Gr-1 antibody leads to susceptibility to Lm infection. The purpose of these studies is to delineate differences in function between neutrophils and monocytes during Lm infection. Neutrophils obtained from the bone marrow, liver and spleen of C57BL/6 mice were more effective at phagocytosis of Lm in comparison to monocytes as they had a higher total bacteria MFI than the monocytes. To determine differences in the ability of the cells to keep bacteria contained in the phagosome, the cells were infected with a strain of Lm that only expresses GFP when the bacteria escapes out of the phagosome into the cytosol. Comparison of the MFI of total bacteria present vs escaped bacteria showed that monocytes allowed for more bacteria to escape in comparison to neutrophils. Therefore, monocytes are less effective at bacterial containment in comparison to neutrophils. To ascertain differences in killing ability, bone marrow neutrophils and monocytes were sorted for a killing assay and neutrophils were also more effective than monocytes at bacterial killing. In conclusion, although both cell types are important for protection during Lm infection, neutrophils appear to be essential for protection as they are more effective at phagocytosis, phagosomal containment and bacteria killing. Future studies, such as measurement of ROS/RNS as well as cytokine production, will aid in further defining specific functional differences between neutrophils and monocytes during intracellular bacterial infection.
Anaphylatoxin receptor C3aR on platelets participates in platelet function and links innate immunity with thrombosis
Authors: Sauter Reinhard Joerg , Sauter Manuela , Reis Edimara S. , Emschermann Frederic , Nording Henry , Kraft Peter , Mauler Maximilian , Muenzer Patrick , Rheinlaender Johannes , Edlich Frank , Schäffer Tilman E , Meuth Sven G , Duerschmied Daniel , Borst Oliver , Kleinschnitz Christoph , Lambris John D , Langer Harald 
Published: January 2023

Abstract

Background
Beyond the superficial function of blood coagulation, platelets play an important role in the genesis of vascular inflammatory processes. Interestingly, platelets express the complement receptor C3aR. Here, we examine the role of the complement receptor C3aR on platelets for platelet function and in diseases.

Methods
We detected the expression of C3aR on murine and human platelets using western blot and flow cytometry. We examined proteins, that are in close connection to the C3aR receptor on platelets by mass spectrometry to elucidate the intracellular signaling. We examined the role of the platelet C3aR for platelet function using different platelet function tests. To investigate the relevance of our findings in vivo, we made use of mice that are deficient for C3aR. After performing bleeding time and intravital microscopy experiments, we induced myocardial infarction and stroke in knockout animals.

Results
We found that C3aR on platelets plays an important role in platelet function and thrombus formation. We discovered that the complement activation fragment C3a regulates bleeding time after tail injury and thrombosis using C3aR−/− mice or C3−/− mice with re-injection of C3a. After induction of a myocardial infarction or stroke in mice, C3aR−/− mice showed a better outcome in comparison to WT mice. When analyzing the intracellular signaling, we discovered that those effects were PI3 kinase and Rap-1 dependent.

Conclusions
Taken together, we identified the C3a receptor on platelets as an important player in platelet function and thrombus formation. Linking the systems of innate immunology and hemostasis, the C3a receptor on platelets could be a possible therapeutic target in diseases featuring thromboinflammation.
Monocytes subsets and cytokine levels in chronic Chagas disease
Authors: González John M , Gómez-Olarte Sergio , Bolaños Natalia , Echeverry Mariana , Rodríguez Ayda , Cuellar Adriana , Puerta Concepción J. , Mariño Alejandro 
Published: January 2023

Abstract
Monocytes are classified according to CD14 and CD16 expression into classical, intermediate and non classical. Variations in monocytes subsets are involved in the pathogenesis of protozoan and helminthic infections. This study assessed the relationship of monocyte subsets percentages and the level of cytokines in blood from Colombian chagasic patients. Donors included asymptomatic or indeterminate (IND), symptomatic or chronic cardiac chagasic (CCC) and heart transplant (HTCC) patients; also, non-chagasic cardiopathy patients (NCC) and healthy individuals (HI) as controls. Peripheral blood mononuclear cells (PBMCs) were isolated. Fc receptors were blocked using anti-CD16/CD32 and human AB serum. Cells were labeled with antibodies for CD14, CD16 and HLA-DR, and acquired in a flow cytometer. Cytokines were measured in plasma with a Human M1/M2 Macrophage kit. Comparisons were done with Kruskal-Wallis followed by Dunn’s post hoc test and correlations were evaluated by Spearman’s coefficient. Percentages of CD14+ CD16+ and CD14+ HLA-DR+ monocytes were higher in patients with heart involvement (CCC, HTCCC, and NCC). Percentage of intermediate monocytes (inflammatory) increased in CCC patients and was positively correlated with IL-6 concentration and negatively correlated with IL-12p40 levels. IND donors had higher percentages of classical monocytes and an increased production of CCL17, and they positively correlate. The results suggest that variations in the monocyte subsets and cytokines levels might be associated with protection (classical monocytes and CCL17) or the development (intermediate monocytes and IL-6) of chagasic myocardiopathy
Vitamin D promotes anti-microbial activity of macrophages via Complement Receptor Immunoglobulin
Authors: Small Annabelle , Harvey Sarah , Kaur Jaspreet , Putty Trishni , Quach Alex , Munawara Usma , Hii Charles , Ferrante Antonio 
Published: January 2023

Abstract
Vitamin D deficiency remains of major global concern, affecting up to half of the population at some stage of life. Although the use of vitamin D to treat infections has been studied over several decades, the mechanisms involved still remain to be elucidated. There has been a major focus on the effects of vitamin D on innate immunity and macrophages, one of the few cell types that can synthesize active vitamin D. Here, we examined whether vitamin D exerts its anti-microbial effects through Complement Receptor Immunoglobulin (CRIg), a phagocytosis-promoting receptor unique to macrophages. Using a series of in vitro culture methods of human macrophages, we show that CRIg expression by macrophages is increased at the mRNA and protein level by the active derivative 1,25-dihydroxyvitamin D (1,25D), while having no effect on the expression of the classical complement receptors, CR3 (CD11b) and CR4 (CD11c). This upregulation of CRIg was associated with an enhanced anti-microbial capability by the cell against the pathogens Staphylococcus aureus and Candida albicans. Furthermore, using the synthetic triacylated lipopeptide Pam3CSK4, we show that macrophages require activation to convert vitamin D to the active 1,25D, which then in turn acts in an autocrine manner to upregulate expression of CRIg. These findings suggest that a major innate defense mechanism against both bacterial and fungal pathogens controlled by vitamin D is through the regulation of CRIg expression in macrophages.
Mitochondrial alterations in NK lymphocytes from ME/CFS patients
Authors: Silvestre Isabel Barao , Dagda Raul Y , Dagda Ruben K , Darley-Usmar Victor 
Published: January 2023

Abstract
Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a disease characterized by profound fatigue, flu-like symptoms, trouble concentrating, and autonomic problems, all of which worsen after exertion. ME/CFS patients have impaired natural killer (NK) cell activity. NK lymphocytes are a critical first defense against viruses and cancer. ME/CFS patients have difficulties controlling viral infections and many develop non-Hodgkin’s lymphoma. Mitochondrial metabolism is crucial for immune cell function. Mitochondria dysfunction has been previously reported in ME/CFS, but it is not known whether the NK cells of these patients have altered mitochondrial metabolism that affect their activity and contribute to ME/CFS pathogenesis. More importantly, there is currently no efficient method to diagnose ME/CFS or assess efficacy of therapeutic interventions. The Bioenergetic Health Index (BHI) has been developed as promising and reliable surrogate readout of human health by measuring the bioenergetic status of immune cells. Variations in bioenergetic function in patient’s immune cells can reflect both metabolic stress and the mutable role of these cells in ME/CFS immunity and pathogenesis. In our study, we observed that the two main energy-generating mitochondrial pathways, oxidative phosphorylation and glycolysis (bioenergetics parameters), are deregulated in ME/CFS NK cells and in PBMCs. Moreover, we observed alterations in the morphology and membrane potential of the mitochondria of NK cells. These mitochondrial features can affect NK cell function and contribute to the severity of disease. To date, this is the first metabolism assessment of NK cells in ME/CFS and as potential new diagnostic tool for the disease.
Unique Innate Functions of Fetal Macrophage Populations
Authors: Prince Lawrence Stephen , Lakhdari Omar , Anderson Kathryn 
Published: January 2023

Abstract
In fetal and newborn tissues, macrophages play key roles in generating the innate immune response to pathogens. Distinct macrophage populations arise from hematopoietic precursors in the embryonic yolk sac and fetal liver. Here we tested the hypothesis that fetal macrophage populations possess unique innate immune function based on their cellular origin. Innate immune activation following TLR agonist exposure was tested using FACS sorted fetal macrophage populations or total single cell suspension from fetal lung or fetal liver. TLR agonists increased inflammatory cytokine expression in CD11bHI fetal liver macrophages. However F4/80HI yolk sac derived macrophages failed to respond to TLR activation and expressed very low levels of both Il1b and Il6. Similar data were obtained with ELISA measurement of secreted IL-1beta and IL-6 protein. When total liver cells were treated with TLR agonists, again IL-1beta expression was restricted to CD11bHI macrophages. F4/80HI macrophages from the yolk sac were also less likely to phagocytose labeled E. coli. Expression of multiple TLRs was low or undetectable in F4/80HI macrophages, suggesting a unique overall functional program for this distinct macrophage population. Expression profiling showed similar levels of multiple macrophage signature genes in CD11bHI and F4/80HI cells. However expression of C1q family members and Igf1 were much higher in F4/80HI macrophages. Expression of these genes was more consistent with an anti-inflammatory phenotype and removal of damaged cells during developmental morphogenesis. These important mechanistic differences suggest important cellular and molecular strategies for treating neonatal inflammatory disease.
A novel quorum-sensing controlled Type I Effector of Pseudomonas aeruginosa, TesG, suppresses host immune response during chronic infection
Authors: Zhou Xikun , Zhao Kelei , Li Jing , Zhang Xiuyue 
Published: January 2023

Abstract
Pseudomonas aeruginosa is a versatile gram-negative pathogen with intricate intracellular regulatory networks that are responsible for a variety of acute and chronic diseases. The survival strategy of this microorganism during pathogenic process especially in causing chronic infections still remains largely elusive. By using in situ RNA-sequencing, here we show that P. aeruginosa undergoes a large-scale transcriptional reprogramming during lung infection. Specifically, more genes of the TCA cycle, oxidative phosphorylation, nucleotide metabolism, T3SS, and two-component system were up-regulated in acute lung infection, while more genes of lipid metabolism, amino acid metabolism, ABC transporters, the T6SS, the QS system, and biofilm formation were up-regulated in chronic lung infection. Notably, a novel virulence factor TesG (PA4141), which is dominated by the vital quorum sensing (QS) system and secreted by the adjacent type I secretion system, can suppress host inflammatory response and remarkably facilitate the development of chronic lung infection. TesG enters alveolar macrophages by clathrin-mediated endocytosis and therefore suppress subsequent adhesion and phagocytosis, as well as the secretion of cytokines and chemokines of macrophages. Mechanically, TesG can bind to and inhibit the activity of eukaryotic small GTPase RhoA by blocking the junction of RhoA with the Rho-guanine nucleotide exchange factor PDZ-RhoGEF. Overall, the characterization of TesG in our current study reveals a new functional aspect of bacterial QS system during host-pathogen interaction, and may open a new avenue for further mechanistic study of chronic respiratory disease and the development of antibacterial therapy.
Rapidly evolving PARP proteins act as both positive and negative regulators of the antiviral response
Authors: Ryan Andrew , Schwerk Johannes , Soveg Frank , Savan Ram , Daugherty Matthew 
Published: January 2023

Abstract
Viral manipulation of cellular post-translational modifications (PTMs) can be key to their survival and replication. One understudied PTM that has been implicated in the antiviral response is ADP-ribosylation. To manipulate this modification, several viral families encode for a macrodomain capable of binding and removing ADP-ribosylation. Importantly, disruption of this function can lead to reduction in pathogenesis or increases in sensitivity to the host interferon response. While the family of host proteins capable of catalyzing ADP-ribosylation, known as PARPs, is large, a subset show multiple signs of rapid evolution, including gene duplication and loss as well as recurrent sequence changes. Focusing in on these genes, we have found that the long isoform of PARP13 is acting directly to inhibit Sindbis virus, a member of the macrodomain-containing alphavirus family. The full antiviral activity requires the presence of the PARP domain in addition to proper localization. In contrast to this, the short isoform acts as a negative regulator of the interferon response by binding and degrading Interferon mRNAs. The balance between antiviral and proviral functions creates a novel dynamic that is potentially more resistant to viral antagonism. We are now exploring the role of ADP-ribosylation in modulating these two phenotypes.
Neutrophil maturation and their response to infectious pathogens are regulated by microbiota
Authors: Gadjeva Mihaela , Kugadas Abirami , Petenkova Anastasia , Geddes-McAlister Jennifer , Mansour Michael K , Sykes David 
Published: January 2023

Abstract
It has long been considered that a neutrophil’s response to various infectious challenges is innately pre-determined. Here, we provide data that demonstrates that neutrophil proteomes are modulated by the microbiota. We found that the proteomic signatures of mature neutrophils derived from germ free (GF) and specific pathogen free (SPF) mice were significantly different. In the absence of microbiota, mature neutrophils lacked GM-CSF-driven priming.
To identify molecular pathways, we set-up an in vitro system where neutrophil progenitors were transduced with lenti-guides to knock-down key microbiota-driven pathway gene targets. GF-serum exposed neutrophil progenitors did not mature efficiently and had compromised bactericidal properties when compared to progenitors matured in SPF-derived serum. To identify which of the microbiota-driven proteins directly impacted bactericidal functions of neutrophils, we knocked out 19 candidates and tested their killing efficacy. Among all tested clones, one demonstrated a superior inhibition of neutrophil’s bactericidal capacities. Excitingly, this protein had no previously identified function: the knock down of prenylcysteine oxidase-like 1 (pcyox 1l) protein reduced neutrophil’s ability to kill efficiently P. aeruginosa in vitro due to diminished ROS release. Hence, we identified a novel mechanism for microbiota-driven control of innate immunity.
Cumulatively, the data support the concept that microbiota affects neutrophil maturation by defining not only the quantity, but also the quality of mature neutrophils. We predict that neutrophil responses can be specifically tailored to pathogens.
Suppression of cGAS-STING- and RIG-I-MAVS-mediated innate immune responses by Epstein-Barr virus-encoded tegument protein BPLF1 through de-ubiquitination
Authors: Lui Wai Yin , Yuen Kit-San , Jin Dong-Yan 
Published: January 2023

Abstract
Epstein-Barr virus (EBV) is the first human oncogenic virus identified and it is etiologically linked with 2% of human malignancies such as Burkitt’s lymphoma, Hodgkin’s lymphoma, gastric carcinoma and nasopharyngeal carcinoma (NPC). The prevalence of EBV infection suggests that the virus may have developed effective viral countermeasures to evade host innate immunity. In this project we performed a functional screen to identify EBV deubiquitinase (DUB) BPLF1 as a potent antagonist of type I interferon production induced by DNA sensors cGAS and STING or RNA sensors RIG-I and MAVS. The large tegument protein BPLF1 exhibited a prominent suppressive effect on cGAS-STING-, and TBK1-induced interferon production. This effect disappeared when Cys61 of BPLF1 was substituted with Ala, which rendered its DUB domain catalytically inactive. This indicated the requirement of DUB activity for BPLF1’s innate immunosuppressive property. BPLF1 was an active DUB for both K63- and K48-linked ubiquitin chains on adaptor protein STING, with no ubiquitin linkage specificity. Our findings suggest that EBV large tegument protein BPLF1 mitigates innate immune responses through its DUB activity on STING and other critical components of innate immune signaling. Supported by HMRF 17160822, RGC C7027-16G and AoE/M-06/08.
Activation of human immune cells with cowpea mosaic virus
Authors: Albakri Marwah M , Beiss Veronique , Fiering Steven N , Steinmetz Nicole F , Sieg Scott F 
Published: January 2023

Abstract
Novel approaches to retrieve and enhance immunity against cancer antigens have been established. One promising approach involves the use of virus particles derived from the plant virus, Cowpea Mosaic Virus (CPMV). Injection of CPMV into tumor stimulates systemic antitumor immunity in tumor mouse models and canine patients with tumors. The molecular pathways that account for these effects are not well defined. In these studies, we examine the capacity of CPMV to activate human monocytes. Peripheral blood mononuclear cells were incubated overnight with CPMV and CD14+ monocytes were examined by flow cytometry for expression of various markers. Cells were also incubated with “empty” (RNA-free) CPMV (eCPMV) for comparison. Responses to CPMV were also tested with THP-1 dual reporter cells, which are activated by various surface and cytoplasm pattern recognition receptors ligands except for TLR7. CPMV, but not eCPMV, mediated activation of human monocytes as indicated by induced expression of CD86, PDL-1, HLA-DR, IL-15R, and IP-10. In contrast to positive controls, PAM3CSK4 (TLR1/2 agonist) and LPS (TLR4 agonist), neither CPMV nor eCPMV induced activation of THP-1 cells. Activation of monocytes by CPMV was markedly inhibited by a chemical inhibitor of spleen tyrosine kinase (SYK), a key signaling component of TLR activation pathways. Effects of SYK inhibition were also observed in cells stimulated by a TLR7 agonist, imiquimod, but with different outcomes than CPMV stimulation, depending on the activation index that was assessed. These data demonstrate that CPMV activates monocytes in a manner that is highly dependent on RNA and SYK signaling. Overall, these data raise the possibility that TLR7 may play a role in CPMV adjuvant-like activity.