bluuebunny/crossref_metadata_2025_split huggingface dataset:
CD4+ T cell-derived IL-10 is independent of IL-27 signaling in a recall response. (CCR3P.220)
Authors: Perona-Wright Georgia , Fonseca Nicolette , Redpath Stephen 
Published: January 2023

Abstract
Surviving influenza infection requires a careful balance of pro-inflammatory signals that promote viral clearance and anti-inflammatory signals that prevent immunopathology. IL-10 is a potent immunosuppressive cytokine that is essential to this balance. Evidence suggests that in CD4+ T cells, IL-10 expression is critically dependent on IL-27 signaling. Here we show in vitro and in vivo that CD4+ cells downregulate gp130, the signal transduction component of the IL-27 receptor, upon activation. Gp130 expression remains low throughout CD4+ T cell contraction and memory, and renders the T cells non-responsive to IL-27 stimulation. Despite this, during secondary activation effector CD4+ T cells express IL-10 at a level equivalent to their primary effector counterparts. Cells genetically deficient for il27ra also fail to express IL-10 during primary activation but are equivalent to wildtype cells during a secondary response. Together our data highlight an IL-27 independent mechanism of IL-10 regulation that is unique to secondary CD4+ T cell activation, and plays a decisive role in the balance between effective immunity and immunopathology during influenza-induced respiratory disease.
Premature thymic involution impairs let7 up-regulation in the transition from fetal to adult hematopoietic stem cells in the thymus (HEM4P.236)
Authors: Xiao Shiyun , Zhang Wen , Manley Nancy 
Published: January 2023

Abstract
The postnatal thymus is a highly efficient microenvironment for promoting T cell specification and differentiation. However, hematopoietic stem cells (HSCs) possess age-dependent differences in differentiation potential into T or B cells, with fetal-type HSCs having a higher potential for producing B cells. The switch between fetal- and adult-type HSCs occurs in the perinatal period, associated with a transition from Lin28b to Let7 expression. We found that in Foxn1lacZ/lacZ mutant mice, which undergo premature thymic involution beginning at 1-2 weeks postnatally, the ETP and DN1a/b subsets were immediately and progressively reduced, while thymic B cells showed a transient increase peaking at around 3-4 weeks. Heterochronic chimeras showed that the capacity to produce B cells in mutant thymus was dependent on the age of HSCs, rather than the age of thymus. We further demonstrate that in thymic progenitor B cells, while Lin28b down regulation occurred normally, Let7g up regulation was impaired, repressing differentiation and promoting proliferation of progenitor B cells in Foxn1lacZ/lacZ thymus. Changes in the thymic microenvironment included progressive down regulation of CCL25, accelerated reduction of DL4 and a transient increase in IL7. Taken together, these data show that the switch from fetal-type to adult-type HSCs within thymus is controlled by thymic microenvironment at multiple levels, including lymphoid progenitor entry, fate specification, and differentiation.
Ribosomal protein L22 (Rpl22) controls the development of αβ lineage T cells by regulating ER stress pathways (HEM4P.239)
Authors: Solanki Patel Nehal , Stadanlick Jason , Cecile-Duc Ann , Rhodes Michele , Wiest David 
Published: January 2023

Abstract
While mature αβ and γδ T cells arise from a common CD4-CD8- thymocyte progenitor, the pathways controlling separation of these lineages remain poorly understood. We have identified the ribosomal protein Rpl22, a novel effector that plays a crucial role in αβ T cell development, but is dispensable for γδ T cell development. Indeed, Rpl22-deficiency selectively blocks the development of αβ T cells at the β-selection checkpoint in a p53-dependent manner. Here, we investigate the basis for p53 induction caused by Rpl22-deficiency and its restriction to αβ T cell progenitors. We found that Rpl22 can directly bind and suppress the translation of p53 mRNA, and that the absence of Rpl22 induces p53 through translational de-repression. Rpl22 appears to specifically regulate p53 in αβ T cell progenitors by controlling the activity of signaling processes that induce p53, such as endoplasmic reticulum (ER) stress. αβ T cell development is dependent on the activation of ER stress responses, which are known to induce p53. Pharmacologic exacerbation of ER stress blocks development of αβ, but not γδ T cells. Moreover, Rpl22-inactivation exacerbates signals from all three known ER stress sensors (PERK, Ire1α, and ATF6). Finally, inhibiting the ER stress response mediated by PERK partially restores development of Rpl22-deficient αβ progenitors. Together, our data suggest that Rpl22 regulates αβ T cell development by controlling the physiologic ER stress upon which their development depends.
Characterization of the NOTCH1-driven miRNA network that controls normal human T-cell development. (HEM4P.246)
Authors: Taghon Tom , Van der Meulen Joni , Durinck Kaat , Van de Walle Inge , Mestdagh Pieter , Pipelers Peter , De Preter Katleen , Vandesompele Jo , Thas Olivier , Rondou Pieter , Van Vlierberghe Pieter , Frank Speleman 
Published: January 2023

Abstract
We have recently shown that miRNAs can cooperate with NOTCH1 activation in malignant T-cell lymphoblasts (Mavrakis et al. Nature Genetics 2011), but little information is available regarding NOTCH1-regulated miRNAs that mediate human T-cell development under normal physiological circumstances in the thymus. Therefore, we first screened for miRNAs that positively correlate with NOTCH1, HES1 and DTX1 expression during normal human T-cell development. To select for miRNAs that are directly NOTCH1 regulated, NOTCH1 expressing CD34+ thymic T-cell progenitor cells from two healthy donors were cultured in vitro in either the absence (OP9-GFP) or presence of four different NOTCH1 ligands (DL1, DL4, J1, J2) and differential miRNA and mRNA expression patterns were monitored. Next, we validated the candidate NOTCH1 driven miRNAs by implementing publically available NOTCH1 ChIP-sequencing data (Wang et al. PNAS 2011). This showed binding of ICN1 to the promotor regions of some putative target miRNAs. To identify key mRNA targets of these NOTCH1-regulated miRNAs, we used an integrated genomic analysis in which we screened for genes with strongly anti-correlated expression patterns to NOTCH1 and its downstream miRNAs that were additionally predicted targets of these NOTCH1-driven miRNAs. Currently, we are validating these miRNA/mRNA interactions and functionally analyzing the roles of these miRNAs and their targets on human T-cell development in the OP9-DL1 system.
The presence of LAG-3 in nonhuman primates undergoing an active Mycobacterium tuberculosis infection (HEM4P.252)
Authors: Phillips Bonnie , Kaushal Deepak 
Published: January 2023

Abstract
Th1 T cells are essential in the immune response against Mycobacterium tuberculosis (Mtb) infections. Lymphocyte activation gene-3 (LAG-3) regulates this response through the diminishment of effector T cells and the impairment of monocyte differentiation. We hypothesize that LAG-3 up-regulation within Mtb infected nonhuman primates (NHPs) will suppress the Th1 portion of the host immune response resulting in conditions that favor the pathogen and create active tuberculosis (TB) within the host. Here we are studying LAG-3 expression in rhesus macaques infected with aerosolized Mtb. We have chosen the macaque model due to their similarities to humans in the spectrum of TB disease, as well as the architecture of Mtb induced lung granulomas. Previous studies have implied that LAG-3 may have a role in the activation of Mtb infections. There is increasing evidence that up-regulation of LAG-3 occurs in the lungs of animals experiencing TB activation. Further investigation of the lung tissue of these infected animals with fluorescent immunohistochemistry visualized with confocal microscopy has illustrated LAG-3 to be largely present within the outer periphery of the lung. Cells expressing LAG-3 have shown to include T cells and NK cells, with large numbers of these cells appearing in close vicinity to certain populations of antigen presenting cells. These results show that in animals undergoing TB activation, LAG-3 has potential to play an immunomodulatory role in this process.
Type-2 innate lymphoid cells facilitate antigen-induced CD4+ TH2 cell immune response that exacerbates chronic allergic asthma (HYP7P.291)
Authors: Liu Bo , Lee Jee-Boong , Chen Chun-Yu , Burwinkel Karen , Wang Yui-Hsi 
Published: January 2023

Abstract
Type-2 innate lymphoid cells (ILC2s) and acquired CD4+TH2 and TH17 cells were shown to contribute to the pathogenesis of allergic asthma; however, their relative roles in mounting antigen recall response that exacerbate chronic allergic asthma remain elusive. Here we reported that repeated OVA re-challenge induced significant increases of eosinophil, not neutrophil accumulation and serum OVA specific IgE and IgG1 in rested mice that previously developed allergic asthma. Subsequent analysis revealed that these rested mice with allergic asthma preferentially mounted elevated OVA specific CD4+TH2 cell response against intranasal OVA re-challenge, while the frequency of lung OVA specific TH17 cells or ILC2s remained constant. While ILC2s and TH17 cells developed normally, STAT6 KO mice that lacked TH2 cell compartment or mice ablated of CD4+ T cells failed to mount allergic recall response to OVA re-challenge. Notably, we observed that cocultured ILC2s could greatly enhance TH2 cytokine production by OVA specific TH2 cells after OVA stimulation ex vivo. Indeed, mice co-transferred with ILC2s and OVA specific TH2 cells exhibited significantly increased inflammatory cell infiltration and goblet cell hyperplasia, compared to those transferred with ILC2s or TH2 cells alone. Collectively, our results suggest that antigen re-exposures preferentially induce lung resident TH2 cells to mount antigen recall immune response that can be enhanced by ILC2s to exacerbate allergic inflammation
Suppression of established IgE-mediated food allergy with anti-FcεRIα mAb (HYP7P.310)
Authors: Krishnamurthy Durga , Khodoun Marat , Jensen-Jarolim Erika , Finkelman Fred 
Published: January 2023

Abstract
Food allergy, in mouse models, is mediated by mast cells, FcεRI and IgE. We recently demonstrated that rapid desensitization with a hamster mAb to mouse FcεRIα (MAR-1) safely suppresses IgE-mediated anaphylaxis (JACI, 131:1555-64, 2013). Consequently, we evaluated whether the same approach could suppress established food allergy in BALB/c mice that had been sensitized intraperitoneally with ovalbumin/alum or egg white/alum and challenged repeatedly by oral gavage with ovalbumin or egg white until they had developed shock and diarrhea. Treatment of these mice with 50 µg of MAR-1 every 4 days suppressed both the induction of hypothermia by oral gavage with ovalbumin or egg white and mast cell MMCP1 secretion by 85-90% and decreased the incidence of diarrhea by 70-85%. Although MAR-1 suppression of food allergy was eventually limited by mouse development of IgG antibodies to hamster IgG, this could be prevented by injecting mice with anti-CD4 mAb (GK1.5) at the time of the initial MAR-1 injection. Although GK1.5, by itself, had little effect on established food allergy, the combination of MAR-1 plus GK1.5 completely suppressed the hypothermia, diarrheal, MMCP1, IL-4 and IL-13 responses to oral gavage with ovalbumin or egg white. These observations suggest that rapid desensitization, followed by continuing treatment with a non-immunogenic (humanized) anti-FcεRIα mAb might effectively suppress IgE-mediated food allergy in people with this disorder.
FADD and caspase-8 mediate priming and activation of the canonical and non-canonical Nlrp3 inflammasomes (INC5P.321)
Authors: Gurung Prajwal , Kanneganti Thirumala-Devi 
Published: January 2023

Abstract
The Nlrp3 inflammasomes are essential for protection against several infections and autoimmune diseases. Despite the plethora of research focused on understanding the roles of NLRP3 in various disease settings, the mechanisms controlling its activation remain enigmatic. Herein, we show through genetic studies that FADD or caspase-8 is required for both transcriptional priming and posttranslational activation of the canonical and non-canonical Nlrp3 inflammasomes. FADD and caspase-8 were required for caspase-1 activation during canonical Nlrp3 inflammasome activation by both soluble (LPS+ATP) and particulate (Silica) ligands. We showed that FADD and caspase-8 also regulate Nlrp3 expression. Furthermore, both FADD and caspase-8 were critical for caspase-11 and caspase-1 activation during non-canonical Nlrp3 inflammasome activation by C. rodentium and E. coli. These requirements of FADD and caspase-8 for caspase-1 activation were specific to the Nlrp3 inflammasome since the activation of Nlrc4 inflammasome by S. typhimurium was not hampered by deletion of FADD or caspase-8. In vivo LPS challenge or C. rodentium infection of FADD or caspase-8-deficient mice resulted in impaired IL-1β production compared to their littermate controls. Thus, our results demonstrate that FADD and caspase-8 are critical mediators of the canonical and non-canonical Nlrp3 inflammasomes.
Impact of obesity on intraepithelial lymphocyte homeostasis (INC6P.350)
Authors: Park Christa , Costanzo Anne , Cheung Kitty , Jameson Julie 
Published: January 2023

Abstract
According to the Center of Disease Control and Prevention, more than one-third of the U.S. adult population is obese. Obesity is caused by overnutrition and accumulation of excess body fat leading to a state of chronic inflammation that impacts the function of epithelial tissues such as the intestine. The intestine consists of villi that increase the overall surface area to digest food and absorb nutrients. The epithelial layer of the villi contains immune cells such as intraepithelial intestinal lymphocytes that are important in maintaining epithelial homeostasis and repairing damaged intestinal tissue. Mice were placed on a high fat diet to define the mechanism by which obesity impacts intestinal epithelia and barrier function. Our data show that obese mice exhibit an increase in the severity of DSS-induced colitis. Using immunofluorescent microscopy we observe an increase in intestinal villi length with a simultaneous reduction in IEL number. The lamina proprial macrophages become skewed toward M1 CD11b+ CD11c+ proinflammatory type macrophages. Short-term diet reduces the severity of colitis for obese mice suggesting that dieting improves intestinal homeostasis in obesity. These data show the detrimental effects of obesity in the small intestine and future studies should focus on finding therapeutic treatments to fully restore IEL number and function to promote optimal intestinal homeostasis and barrier function.
Ectodomain shedding of the NKG2D ligand MULT1 regulates sensitivity to NK cells (INC6P.400)
Authors: Deng Weiwen , Wang Lin , Nice Tim , Lau Stephanie , Zhang Lily , Iannello Alexandre , Raulet David 
Published: January 2023

Abstract
NKG2D is one of the most important activating receptors expressed by NK cells in terms of tumor cell recognition. NKG2D binds to different ligands, and triggers cytolysis and cytokine release by NK cells. Certain human NKG2D ligands can be shed and are thought to inhibit NK-mediated surveillance of cancer. Here we showed that a mouse NKG2D ligand, MULT1, is cleaved efficiently from cells, and accumulates in the serum of tumors and inflammatory diseases. Cleaved MULT1 binds to NKG2D with high affinity (~10 nM). Remarkably, an engineered form of the shed MULT1, when secreted by tumor cells lacking NKG2D ligands, causes tumor rejection, rather than inhibiting it. Rejection is mediated by NK cells and in some cases T cells. Provision of recombinant MULT1 along with B16 melanoma cells resulted in induction of NK function ex vivo and tumor rejection in vivo. We propose a model in which expression of NKG2D ligands by non-tumor cells, persistently stimulate NK cells, resulting in desensitization of the NK cells; interruption of the interaction by soluble MULT1 restores NK cell functionality, causing tumor elimination. Consistent with this model, Rag2-/- mice which also lack NKG2D show higher NK activity than Rag2-/- mice, resulting in better B16 tumor rejection. Our study represents the first instance of NKG2D ligand shedding in the mouse, and provides the first evidence that such ligands are immunostimulatory, reversing the conventional understanding of soluble NKG2D ligands.
Antiviral activity of human OASL is mediated by mimicking ubiquitin chains to activate RIG-I pathway (INM6P.421)
Authors: Zhu Jianzhong , Zhang Yugeng , Cuevas Rolando , Forero Adriana , Dhar Jayeeta , Ibsen Mikkel , Schmid-Burgk Jonathan , Schmidt Tobias , Ganapathiraju Madhavi , Fujita Takashi , Hartmann Rune , Chen Zhijian , Barik Sailen , Hornung Veit , Coyne Carolyn , Sarkar Saumendra 
Published: January 2023

Abstract
Virus infection is sensed in the cytoplasm by RIG-I, which requires RNA and poly-ubiquitin binding to induce type I interferon (IFN), and activate cellular innate immunity. We show that unlike mouse, the human IFN-inducible oligoadenylate synthetases-like (OASL) protein has antiviral activity and mediates RIG-I activation by mimicking polyubiquitin. Loss of OASL expression reduces RIG-I signaling and enhances virus replication in human cells. Conversely, OASL expression suppresses replication of a number of viruses in a RIG-I-dependent manner and enhances RIG-I-mediated IFN induction. OASL interacts and colocalizes with RIG-I, and through its C-terminal ubiquitin-like domain specifically enhances RIG-I signaling. Importantly, inactive RIG-I mutants defective in ubiquitination and polyubiquitin binding still bind to OASL, and their signaling activity is rescued by OASL. Our findings show a novel mechanism by which human OASL contributes to host antiviral responses by enhancing RIG-I activation.
Cytoplasmic LPS activates caspase-11: implications in TLR4-independent endotoxic shock (INM6P.406)
Authors: Miao Edward , Hagar Jon , Powell Daniel , Aachoui Youssef , Ernst Robert 
Published: January 2023

Abstract
Inflammatory caspases, such as caspase-1 and -11, mediate innate immune detection of pathogens. Caspase-11 induces pyroptosis, a form of programmed cell death, and specifically defends against bacterial pathogens that invade the cytosol. During endotoxemia, however, excessive caspase-11 activation causes shock. We report that contamination of the cytoplasm by lipopolysaccharide (LPS) is the signal that triggers caspase-11 activation in mice. Specifically, caspase-11 responds to penta- and hexa-acylated lipid A, whereas tetra-acylated lipid A is not detected, providing a mechanism of evasion for cytosol-invasive Francisella. Priming the caspase-11 pathway in vivo resulted in extreme sensitivity to subsequent LPS challenge in both wild type and Tlr4-deficient mice, whereas caspase 11-deficient mice were relatively resistant. Together, our data reveal a new pathway for detecting cytoplasmic LPS.
Leukotriene B4 dictates sterile inflammation in type 1 diabetes (INM7P.424)
Authors: Serezani Henrique , Filgueiras Luciano , Brandt Stephanie , Wang Sue , Morris David , Wang Zhuo , Mirmira Mirmira , Evans-Molina Carmella , Jancar Sonia 
Published: January 2023

Abstract
Type 1 diabetes (T1D) is characterized by chronic systemic inflammation that could be involved in the enhanced susceptibility to sepsis. The IL-1b/IL-1bR axis drives inflammation in a MyD88-dependent manner, but the molecular mechanisms involved in IL-1b actions in macrophages during T1D are unknown. We hypothesized that leukotriene (LT) B4 promotes IL-1b responsiveness in T1D by enhancing MyD88 expression. Peritoneal macrophages (PMs) from T1D mice expressed higher levels of MyD88 and its transcription factor STAT-1 than PMs from nondiabetic mice. 5-LO expression, LTB4 synthesis and IL-1b levels were also increased in both PM and serum from T1D mice. In vitro and in vivo insulin treatment restored LTB4 and STAT-1/MyD88 levels. Genetic and pharmacologic inhibition of the LTB4/BLT1 axis abolished MyD88 and STAT-1 induction in diabetic mice. ChIP assay showed that AP-1/cJun drove basal STAT-1 levels in an LTB4-dependent manner in T1D. We speculated that high LTB4 levels contribute to enhanced susceptibility to sepsis in T1D. Compared to WT or untreated T1D mice, genetic and pharmacologic inhibition of 5-LO prolonged T1D mice survival after polymicrobial sepsis; associated with decreased blood bacteria and reduced production of proinflammatory cytokines. We conclude that LTB4, by increasing MyD88 and IL-1b levels in a c-Jun/STAT-1 dependent manner, is the driving force involved in inflammation associated with T1D that contributes to high mortality associated to sepsis T1D.
Dual role of Interleukin-37 in the regulation of inflammation triggered by Propionibacterium acnes in human monocytes (INM8P.450)
Authors: Qin Min , Park Andrew , Agak George , Garban Hermes , Kim Jenny 
Published: January 2023

Abstract
IL-37 is an anti-inflammatory cytokine that is highly concentrated in the epidermis. In this study, we sought to investigate the immunomodulatory role of IL-37 in acne pathogenesis. In human monocytes isolated from peripheral blood mononuclear cells, we show that P. acnes upregulates expression of IL-37 in a pathway dependent on Toll-like receptor 2, NLRP3 and caspase-1 signal transduction. Using small interfering RNA to knock down IL-37 gene in monocytes, our results show upregulation of IL-1β, IL-6, and IL-8, and downregulation of IL-10, suggesting anti-inflammatory properties in P. acnes -stimulated monocytes. We demonstrate that IL-37 may have a reversal property when acting extracellularly. Recombinant IL-37 alone and P. acnes both induce IL-1β, IL-6, and IL-8 in a concentration-dependent manner. A greater cytokine response occurs when both IL-37 and P. acnes are used to co-treat monocytes. As we show that IL-37 is released only after cell membrane digest in monocytes but not actively secreted by viable cells, our data suggests a dualistic role of IL-37. While it may be anti-inflammatory intracellularly, IL-37 may act as a pro-inflammatory cytokine when released after cell damage and death. Intracellular IL-37 is a potent inhibitor of P. acnes -induced inflammatory response, yet has a reversal of properties when acting to signal nearby immune cells.
Neutrophils are critical in the pathogenesis of atypical EAE in LysMCre-SOCS3fl/fl mice (IRC5P.471)
Authors: Liu Yudong , Qin Hongwei , Benveniste Etty (Tika) 
Published: January 2023

Abstract
Experimental autoimmune encephalomyelitis (EAE) is an autoimmune disease of the central nervous system (CNS) characterized by demyelination, inflammatory lesions and axonal damage. We previously demonstrated that deletion of Suppressor of Cytokine Signaling 3 (SOCS3) in myeloid cells resulted in atypical EAE with a striking neutrophil infiltration in the brain. In this study, we investigated the role of neutrophils in the pathogenesis of atypical EAE. Kinetics studies show that accumulation of neutrophils in LysMCre-SOCS3fl/fl mice correlate with disease development. Ab-mediated depletion of neutrophils delays the onset of atypical EAE and prolongs survival. Importantly, brain-infiltrating neutrophils display high expression of CXCR2, and produce high levels of CXCL2, CCL2 and nitric oxide (NO). In addition, LysMCre-SOCS3fl/fl recipients develop atypical EAE in Th1- and Th17-adoptive transfer models. Our findings indicate that, in LysMCre-SOCS3fl/fl mice, neutrophils facilitate the disruption of the blood-brain barrier (BBB), and once they gain access to the brain, they play an essential role in the development of atypical EAE by promoting their own recruitment through production of CXCL2, and promoting macrophage recruitment through production of CCL2. More importantly, the activated neutrophils produce high levels of NO, resulting in inhibition of regulatory T-cells, oligodendrocyte damage and axonal degeneration, which leads to atypical EAE in LysMCre-SOCS3fl/fl mice.