bluuebunny/crossref_metadata_2025_split huggingface dataset:
T cell targets in mouse allergy extend beyond the major mouse allergen Mus m 1
Authors: Schulten Véronique MJ , Westernberg Luise , Paul Sinu , Sette Alessandro 
Published: January 2023

Abstract
Mouse allergy is an important disease affecting laboratory workers and inner-city households with increased exposure leading to allergic sensitization and asthma. To date, only one major allergen in mouse, Mus m 1, has been identified. Using a combination of proteomics and bioinformatics, we sought to identify T cell targets in mouse allergic patients.
Mouse urine and epithelial extract were analyzed by 2D- IgE/IgG immunoblots using pooled sera from mouse allergic donors. Mass spectrometry of selected protein spots identified 30 novel antibody reactive proteins. Predicted MHC binding peptides from these novel proteins and mouse homologs to mammalian allergens were screened for T cell reactivity in PBMCs from mouse allergic patients. Overlapping peptides from the major mouse allergen Mus m 1 were screened in parallel.
T cell epitope mapping experiments that responses to Mus m 1 peptides were dominant overall. However, reactivity to mouse peptides homologous to other mammalian allergens was also detected. Very little T cell reactivity against peptides derived from novel proteins was observed.
In summary, our data demonstrates that the cellular and serological targets of the allergic response overlap, with Mus m 1 being the major target for both T cells and IgE antibodies. However, on a serological level, other proteins are also recognized. Furthermore, mammalian allergens with murine homologs may also be of relevance for the T cell response in mouse allergic patients. Identifying the immunological targets in mouse allergy is of high importance since the prevalence of this disease is drastically increasing and candidates for improved diagnostics and immunotherapeutic approached are of growing importance.
Toll like receptor 2 co-stimulation signaling in CD4+ T cells promote TH9 differentiation and function
Authors: Karim Ahmad Faisal , Reba Scott M , Ding Xuedong , Rojas Roxana E 
Published: January 2023

Abstract
We have recently demonstrated that mycobacterial ligands engage Toll like receptor 2 (TLR2) on human CD4+ T cells and up-regulate T-cell receptor (TCR) triggered-Th1 responses in vitro and in vivo. To better understand the role of T-cell expressed TLR2 on CD4+ T cell differentiation and function, we conducted a gene expression analysis of naïve CD4+ T-cells stimulated in the presence or absence of TLR2 co-stimulation. Unexpectedly, naïve CD4+ T-cells co-stimulated via TLR2 show a significant up-regulation of IL-9 mRNA compared to cells co-stimulated via CD28. To further evaluate the impact of T-cell expressed TLR2 on TH9 differentiation, naïve CD4+ T cells were polyclonally stimulated under TH9 polarizing conditions with or without a TLR2 agonist. Upregulation of TH9 differentiation, evidenced by increases in both percent of IL-9 secreting cells and IL-9 in culture supernatants, was observed in cells differentiated in the presence of TLR2 agonist. Also, engagement of T-cell TLR2 up-regulated the percent of IL-9 secreting cells in Ag85B-specific CD4+ T-cells stimulated with cognate peptide in TH9 polarizing conditions. On the other hand, in the absence of TH9-polarizing conditions, TLR2 engagement on CD4+ T-cells had minimal effect on IL-9 secretion and TH9 differentiation. This is likely due to a prominent effect of TLR2 signaling on IFN-γ secretion and TH1 differentiation under non-polarizing conditions. Here we also report that, TLR2 signaling in CD4+ T-cells increased expression of transcription factors BATF and PU.1, which are known to positively regulate TH9 differentiation. These results reveal a novel role of T-cell expressed TLR2 in enhancing the differentiation and function of TH9 T cells.
Activated MLKL functions as signal II of the NLRP3 inflammasome
Authors: Gutierrez Kimberley Diane , Davis Michael , Olsen Tayla M , Oberst Andrew 
Published: January 2023

Abstract
Activation of the NLRP3 inflammasome results in caspase-1 dependent processing and secretion of IL-1β. Inflammasome activation and IL-1β maturation is thought to require two signals: Signal I leads to transcriptional up-regulation of inflammasome components and pro-IL-1β. Various agents such as ATP and nigericin can function as signal II to activate the NLRP3 inflammasome through a mechanism that is thought to involve disrupted ion homeostasis. This in turn leads to IL-1β processing and release, as well as pyroptotic cell death. Notably, the execution of another cell death program, necroptosis, also involves cellular membrane disruption and ion flux, through the action of the protein MLKL. Here, we demonstrate that the execution of necroptosis by MLKL can lead to NLRP3 inflammasome activation and the secretion of bioactive IL-1β. We further show that IL-1β processing is independent from the cell death function of MLKL. This mechanism represents a novel inflammatory signal emanating from necroptotic cells, as well as an unexpected mechanistic cross-talk between necroptosis and inflammasome activation.
The Role of Glutathione Reductase in Neutrophil Respiratory Burst and ERK Signaling
Authors: Liu Yusen , Crowell Sara A. , Chen Ying , Rogers Lynetter K. , Nelin Leif D. 
Published: January 2023

Abstract
Respiratory burst plays a crucial role in the killing of bacteria by phagocytes. During the respiratory burst, NADPH oxidase complexes are assembled on the membrane to produce superoxide, which is then converted to H2O2 for pathogen killing. Glutathione (GSH) is crucial for the detoxification of H2O2 that has diffused into the cytosol. GSH is generated via both de novo synthesis and regeneration from glutathione disulfide. The rate-limiting step in GSH synthesis is catalyzed by γ-glutamate cysteine ligase, composed of a catalytic subunit (Gclc) and a regulatory subunit (Gclm), whereas GSH regeneration is catalyzed by glutathione reductase (Gsr). Mice with a mutation in the Gsr gene exhibit a profound defect in immune defense against bacteria, which is associated with compromised respiratory burst activity. To address the mechanisms underlying the compromised respiratory burst, we purified neutrophils from wildtype (WT) and Gsr−/− and Gclm−/− mice, and assessed their respiratory burst in response to phorbol ester (PMA). Compared to WT neutrophils, Gsr−/− neutrophils exhibited a dramatic decrease in respiratory burst activity. A similar trend was observed in neutrophils derived from Gclm−/− mice, which have 10–40% of normal tissue GSH levels. However, no significant defect in immune defense against E. coli was found in Gclm−/− mice. Cellular fractionation indicated that the NADPH oxidase subunits underwent membrane translocation in response to PMA in both WT and Gsr−/− neutrophils. Interestingly, Gsr−/− neutrophils also displayed a dramatic enhancement in activation of the ERK MAP kinase pathway. Our results indicate that Gsr plays an important role in the regulation of both the respiratory burst and cell signaling in neutrophils.
Macrophages and Plasmacytoid Dendritic Cells Initiate Early Immune Response To Severe Malaria In The Bone Marrow
Authors: Lauvau Gregoire , Spaulding Emily , Fooksman David R , Reizis Boris , Daily Johanna P 
Published: January 2023

Abstract
Malaria still remains a significant global health problem worldwide with approximately 200 million people infected, and half a million deaths every year. Most of these fatalities (80%) occur in children under the age of five, and the latest RTS, S, preventative vaccine trial only exhibited low protective efficacy (below 30%). The blood stage of Plasmodium infection accounts for the clinical symptoms of malaria, yet the immune mechanisms underlying disease outcomes are poorly understood. Here we have analyzed a cohort of severely infected Malawian children and revealed dramatic levels of inflammatory cytokines and extremely robust blood leukocyte activation, notably for CD14+CD16lo CCR2+ inflammatory monocytes, plasmacytoid DCs (pDCs), NK and T cells. We could recapitulate these observations using the Plasmodium yoelii (Py) 17X YM surrogate mouse model of lethal blood stage malaria. Using this experimental system, we demonstrate that type I interferon (IFN) signals as a key cytokine controlling lethal outcomes and immune cell activation. Plasmacytoid dendritic cells represented the main cellular source of type I IFN in the bone marrow and the blood of infected mice. Most interestingly, the activation of pDCs required CD169+ macrophages, and both cell types exhibited prolonged interactions in the bone marrow of infected mice by intravital microscopy. We will present additional data uncovering the molecular sensing pathways controlling these processes. Altogether our study establishes essential molecular pathways and cellular interactions that occur during this significant human parasitic infection, and suggest novel potential therapeutic targets involved in severe malaria.
Alternatively activated brain-resident macrophages acquire and retain inflammatory properties following CNS infection while interacting with effector and memory T cells.
Authors: Rua Rejane , McGavern Dorian B 
Published: January 2023

Abstract
The meningeal and perivascular spaces of the central nervous system (CNS) are inhabited by specialized macrophages, but their homeostatic status and role in orchestrating the immune response against invading pathogens is not well understood. Examination of the naive brain by two-photon microscopy revealed that meningeal and perivascular macrophages are highly dynamic and constantly survey their immediate surroundings similar to microglia. Under steady state conditions, we uncovered that they are maintained in an alternatively activated state, which likely facilitates brain homeostasis. Interestingly, during the development of fatal meningitis induced by lymphocytic choriomeningitis virus, these cells were directly engaged by infiltrating virus-specific CD8+ T cells following acquisition of viral antigen and conversion into an inflammatory phenotype. Mechanistically, microarray analyses revealed that this transition relied on innate cytokine signaling and occurred in the absence of infiltrating inflammatory cells. Using a sub-lethal model of viral meningitis, we observed that despite elimination of previously infected cells, CNS macrophages remained activated for weeks after viral clearance, which was dependent on IFN-g signaling and associated with tissue-resident memory T cell interactions. Collectively, these data indicate that brain-resident macrophages are highly plastic cells that can quickly participate in the antiviral defense against an invading pathogen and can also become imprinted with a prolonged activation program. The inflammatory properties and localization of these cells may explain why most CNS immune responses first develop in the meningeal and perivascular spaces.
Unmasking two stages of interferon signaling in dendritic cells infected with HIV-1
Authors: Johnson Jarrod S , Lucas Sasha , Skelton Stephanie , Nazitto Rodolfo , Amon Lynn , Littman Dan R , Aderem Alan 
Published: January 2023

Abstract
Myeloid dendritic cells (DCs) have the innate capacity to sense pathogens and mount counteroffensive responses, which include the production of type I and type III interferons (IFN). In the case of HIV-1 infection, DCs can internalize and present viral antigens, but the majority of DCs are not productively infected due to restriction at the level of reverse transcription. Consequently, DCs do not efficiently ‘sense’ HIV-1, fail to produce IFN, do not mature, and cannot program appropriate adaptive immune responses. To improve our understanding of how IFN and cell maturation are regulated in monocyte-derived DCs, we have used systems analyses to study how DCs respond to HIV-1 after removing the block to reverse transcription with the lentiviral protein Vpx. We have profiled changes in open chromatin during infection using an assay for transposase-accessible chromatin (ATAC-seq), and have tracked the kinetics of gene expression in parallel. Using antiretroviral drugs and virus mutants to separate stages of the life cycle, we have determined that at least two signals cooperate to drive innate immune responses during HIV-1 infection: the first coming from the cytoplasmic sensor, cGAS, which is known to recognize reverse transcribed HIV cDNA, and the second from an unrelated pathway engaged after virus integration. Moreover, by interrogating infection in combination with a battery of classic innate agonists we have found that HIV-1 primes DCs to produce IFN, even in the presence of certain antiretroviral drugs. Our studies demonstrate that robust IFN production in response to HIV-1 infection depends on the coordinated action of distinct transcription factors and illuminate key pathways that regulate innate immunity in myeloid cells.
The impact of surgical wounding on pulmonary infection
Authors: Xu Yun , Crane Meredith J. , Henry William L. , Albina Jorge E. , Jamieson Amanda M. 
Published: January 2023

Abstract
Post-surgical pneumonia happens frequently in hospitals and is prevalent in intensive care unit (ICU) patients. Its prevalence is correlated with the length of stay in hospital, the degree of trauma, and importantly, the mortality. While it is clear that there is an increased risk of acquiring pneumonia in post-surgical patients, not much is known about the detailed impacts of surgical wound healing on pulmonary infections and its immunity. Therefore, it is necessary to understand why pneumonia is common after surgery, and how the wound healing process influences the lung. Wound healing is a complicated process involving various immune cells, such as neutrophils, monocytes, and macrophages. Immune cells essential for proper wound healing are also crucial for the host to recognize, fight and resolve pulmonary infection. We have combined two wounding models (dorsal polyvinyl alcohol sponge implantation and excisional tail wounding) with one pulmonary pathogen—Influenza A Virus (IAV)—to investigate the immune responses at the two distinct sites. From our investigation, we have found that 1) wounding does not influence the clearance of IAV; 2) wounding increases immune cell infiltration into the lung; 3) wounding increases the levels of cytokines and chemokines in the lung; and 4) IAV infection delays wound healing. The future direction of this project will focus on investigating how the changes in immune cell infiltration, cytokines, and chemokines happen, and what renders the host more susceptible to pulmonary infections. In addition, we will explore the interactions between wounding and pulmonary Streptococcus pneumoniae infection and the general biological mechanisms behind the clinical phenomena.
NLRP12 limits TNFα-induced apoptosis of monocyte progenitor cells during emergency hematopoiesis
Authors: Linz Brandon M , Brickey W June , Ting Jenny P , Cairns Bruce A , Maile Robert 
Published: January 2023

Abstract
The NLR family member NLRP12, expressed in peripheral leukocytes and bone marrow progenitor cells, is implicated in controlling the response of the innate immune system by suppressing non-canonical NfκB signaling. Given the hematopoietic system’s ability to respond to insults by rapidly increasing myeloid cell production, and the importance of tightly controlled cytokine regulation during these processes, we hypothesized NLRP12 to be a key regulator of the innate immune system’s reconstitution following a hematopoietic emergency. To test this, wild type and Nlrp12−/− C57BL/6 female mice underwent a radiation-thermal combined injury (RCI) consisting of a 20% total body surface area, full thickness contact burn in addition to receiving a single whole-body dose of 5 Gy γ-radiation. Following injury, Nrlp12−/− mice showed a three-fold increase in specific apoptosis of granulocyte-monocyte progenitor cells leading to a reduction in the total number of bone marrow cells and thus systemic leukopenia. We also observed that the lack of NLRP12 led to elevated levels of TNFα systemically following injury. Utilization of a neutralizing antibody against TNFα following injury abrogated the granulocyte-monocyte progenitor cell apoptosis and leukopenia seen in vehicle-treated mice. These data lead us to conclude that NLRP12 acts as a suppressor of TNFα signaling during emergency hematopoiesis; a novel finding, since no member of the NLR family has been previously found to interact with TNFα signaling.
Inflammasome dependent IL-1β secretion requires Dnase1L3 activity
Authors: shi guilan , Abbott Kennady , Salter Russell D , Keyel Peter A 
Published: January 2023

Abstract
Inflammation is driven by inflammatory cell death and the secretion of pro-inflammatory cytokines like IL-1β and alarmins like High Mobility Group Box Protein 1 (HMGB1) by the inflammasome. The inflammasome is a cytosolic multiprotein complex that typically contains a Nod-like receptor (NLR), like NLRP3 or NLRC4, and the adaptor ASC which links to caspase-1 for activation. How signals from the cytoplasmic NLR induce nuclear ASC and HMGB1 translocation into the cytosol for inflammasome function remains elusive. Here we hypothesize that Dnase1L3 (DNase γ), a Ca2+/Mg2+-dependent endonuclease, facilitates inflammasome-mediated release of cytokines and alarmins. When we treated murine macrophages with the Dnase1L3 inhibitors Fmoc-D-cyclohexylalanine (FCA) or pontacyl violet 6R (PV), HMGB1 and IL-1β release were inhibited following NLRP3 or NLRC4 stimulation. FCA and PV did not directly inhibit Casp1. We confirmed the specificity of the inhibitors using RNAi silencing of Dnase1L3 in THP-1 cell lines. Interestingly, pyroptosis was only slightly blocked by Dnase1L3 inhibition. Mechanistically, we found that ASC nuclear translocation and speck formation was impaired following FCA treatment, as was Casp1 cleavage. These data suggest that Dnase1L3 inhibition prevents Asc release from the nucleus. This demonstrates that pyroptosis and cytokine release can be mechanistically separated. Taken all together, these data show that Dnase1L3 is necessary for inflammasome-mediated release of cytokines and alarmins.
Hepatitis C virus hijacks host microRNAs to dampen antiviral interferon signaling
Authors: Jarret Abigail P , McFarland Adelle P , Horner Stacy M , Kell Alison M , Hong MeeAe , Badil Samantha , Joslyn Rochelle C , Baker Darren , Carrington Mary , Hagedorn Curt , Gale Michael J , Savan Ram 
Published: January 2023

Abstract
Hepatitis C virus (HCV) is a hepatotrophic ssRNA virus that infects over 160 million people worldwide and 60–80% of HCV cases will persist to a chronic infection, a serious risk factor for liver diseases. We recently discovered that HCV infection of hepatocytes induces expression of two microRNAs (miRNAs), miR-208b and miR-499a-5p. We found that these miRNA are capable of decreasing IFNL2 and IFNL3 expression to aid viral replication. Here we show that miR-208b and miR-499a-5p block type I IFN signaling in HCV-infected hepatocytes by directly targeting and down regulating the interferon (alpha, beta and omega) receptor 1 (IFNAR1) mRNA. Inhibition of these miRNAs during HCV infection of hepatoma cells rescued expression of IFNAR1 and improved the antiviral response to exogenous type I IFN. Interestingly, prolonged treatment of HCV-infected hepatocytes with type I IFNs led to a synergistic induction of miR-208b and miR-499a-5p, suggesting a critical role for type I IFN in the regulation of these miRNAs. As miR-208b and miR-499a-5p can target and suppress the IFNL3 risk allele, it is possible that increased miRNA expression following IFN treatment may partly explain why this genotype associates with poor response to IFN based therapies. Collectively these data define a new role for miR-208b and miR-499a-5p as HCV-induced suppressors of type I IFN signaling and add to our understanding of HCV immune evading strategies.
Cognitive impairment, blood-brain barrier breakdown, and pro-inflammatory mediators in neonatal Escherichia coli K1 meningitis.
Authors: Barichello Tatiana , Generoso Jaqueline , Simoes Lutiana , Florentino Driélly , Michels Monique , Comim Clarissa M , Petronilho Fabricia , Quevedo Joao , Dal-Pizzol Felipe , Teixeira Antonio 
Published: January 2023

Abstract
Neonatal Escherichia coli meningitis is an important cause of mortality and morbidity in newborns. We evaluated cytokines, oxidative damage/enzymatic defense, BDNF levels, blood-brain barrier (BBB) integrity in the hippocampus of neonatal Wistar rats following E. coli K1 meningitis and subsequent behavioral parameters in adulthood. Neonatal male rats received an intracisternal injection of placebo or E. coli K1 suspension. First: at 6, 12, 24, 48, and 96 h were evaluated cytokines, oxidative damage/enzymatic defense, BDNF levels, and BBB integrity. TNF-α, IL-4, IL-6, IL-10, BDNF, and protein carbonylation were produced mainly in the first 6 to 96 h. Myeloperoxidase, thiobarbituric acid reactive-substances, nitrate/nitrite, and sulfhydryl group were produced at 24 h. Superoxide dismutase decrease in the first 6 h, catalase activity levels did not change and the BBB breakdown at 12 h after meningitis induction. Second: sixty days after meningitis were evaluated behavioural parameters (neonatal rats received antibiotic treatment): habituation to the open-field, step-down inhibitory avoidance, and continuous multiple-trials step down inhibitory avoidance tasks. In the habituation to the open-field and in the step-down inhibitory avoidance tasks there were no differences between training and test session in the meningitis group, demonstrating memory impairment. In the continuous multiple-trials step-down inhibitory avoidance task, there was a significant increase in the number of training trials required to reach the acquisition criterion in the meningitis group when compared to the control group, indicating a learning impairment. Neonatal E. coli K1 meningitis causes learning and memory impairments in adulthood.
Estimating total numbers of Mycobacterium tuberculosis in lymph nodes of cynomolgus and rhesus macaques
Authors: Ganchua Sharie Keanne C , Cadena Anthony M , Flynn JoAnne L 
Published: January 2023

Abstract
Tuberculosis (TB) is predominantly thought of as a lung disease. However, in classic pathology studies, a thoracic lymph node is often infected in addition to the lungs. Furthermore, lymphadenitis is common in children infected with Mycobacterium tuberculosis (Mtb). In our non-human primate model, at least one lymph node is infected in nearly all macaques. However, rhesus macaques have substantially more lymph node involvement than cynomolgus macaques, and this often leads to clinical deterioration. To better understand the role of lymph nodes in TB, as well as the differences between these species, we quantified the total number of Mtb genomes (live and dead bacteria) in the lymph nodes at 4 and 12 weeks post-infection (p.i.). Mtb burden in the lymph nodes was not significantly different between cynomolgus and rhesus macaques, as well as between 4wk and 12wk p.i.. We then compared the number of Mtb genomes with the number of viable bacteria to determine the degree of bacterial killing in these tissues. Overall, bacterial killing in lymph nodes was very low, compared to lung granulomas. However, the 12wk p.i. rhesus macaques had significantly less Mtb killing in their lymph nodes than the 4wk p.i. rhesus and 12wk p.i. cynomolgus macaques, which could in part explain the greater lymph node involvement in rhesus macaques. The level of bacterial killing between intact and effaced (necrotic) lymph nodes was similar; however, there was a trend of increasing Mtb burden as the effacement increases. Some lymph nodes without culturable bacteria were found to have Mtb genomes present, suggesting lymphatic spread. Our preliminary data suggest that lymph nodes may play a role as a bacterial reservoir and as a means of bacterial dissemination and reactivation.