bluuebunny/crossref_metadata_2025_split huggingface dataset:
T cell intrinsic deletion of the adenomatous polyposis coli gene causes homeostatic proliferation and inflammatory bowel disease (BA11P.142)
Authors: Wong Chun-Shu , Chen Chong , Wu Qi , Liu Yang , Zheng Pan 
Published: January 2023

Abstract
Accumulating data demonstrate a strong association between lymphopenia and autoimmune diseases. However, to our knowledge, none of the known single gene defects that cause lymphopenia are sufficient to cause autoimmune diseases. In addition, the intracellular programing involved in lymphopenia-driven homeostatic proliferation (HP) remains to be elucidated. Using a conditional knockout of adenomatous polyposis coli (Apc) under the control of CD4-cre, we have previously reported that T-cell lineage-specific deletion of the Apc gene causes severe lymphopenia, due to naive T cell death, in part through activation of the cMyc gene. Here, we show that Apc deletion causes both T cell activation, lymphopenia-driven HP. Using this mouse model, we studied the association between lymphopenia-driven HP, and autoimmune diseases. We showed that APC deficiency and the resulting activation of Wnt signaling in T cells causes a fatal inflammatory bowel disease with Crohn’s disease-like pathology. Moreover, using T cells with targeted mutation of beta-catenin, we found that lymphopenia-drivinen HP depends on activation of beta-catenin in T cells, thus providing a missing link between Wnt signaling and homeostatic proliferation. Development of autoimmune diseases requires lymphopenia. This data provide the first genetic evidence that a T-cell intrinsic single-gene defect is sufficient to cause lymphopenia, homeostatic proliferation and autoimmune diseases.
CD4+CD40+ T cells (Th40) drive a rapid and severe form of experimental autoimmune encephalomyelitis (BA11P.123)
Authors: Vaitaitis Gisela , Waid Dan , Wagner David 
Published: January 2023

Abstract
The CD40-CD154 dyad is critically involved in autoimmune diseases including Multiple Sclerosis (MS) and Type 1 Diabetes (T1D). CD4+CD40+ T cells, Th40, are necessary and sufficient to establish T1D in the mouse model. In the Experimental Autoimmune Encephalomyelitis (EAE) mouse model of MS, CD4 T cells are known to play a dominant role in disease development, however, the contribution of Th40 cells has not been determined. Here we reveal that the EAE induction regimen, specifically the Freund’s adjuvant (CFA), causes a significant expansion of Th40 cells, which in turn play a major role in EAE development. While expansion of Th40 cells is not dependent on specific antigen, the precipitation of central nervous system disease symptoms is MOG-antigen dependent, shaping a different TCR repertoire. We show that surface expression of CD40 on T cells is associated with a more rapid and severe disease course. Th40 cells are present in lesions in the brains and spinal cords of EAE mice and their cytokine profile is skewed toward IFNγ. In EAE facilitated by CD4+CD40- T cells, where disease develops with significantly slower kinetics and lesser severity, the cytokine profile is skewed more towards IL-17. Primary Th40 cells can adoptively transfer EAE, without prior in-vitro expansion, requiring only the injection of CFA in the recipient mice. These data demonstrate the importance of T cell CD40 and its relation to differential expression of IFNγ and IL-17 in EAE disease induction.
Dual roles of GM-CSF in modulating NK-cell migratory properties (CAM4P.147)
Authors: Andalur Nandagopal Saravanan , Upreti Deepak , Santos Susy , Chyi Su Ruey , Ball Blake , Lin Francis , Kung Sam 
Published: January 2023

Abstract
Background: Natural Killer (NK) cells play a key role in innate immunity against viral, microbial infections and transformed cells and their migration for effector function to peripheral tissues or inflamed lymph nodes are tightly regulated. Of interest, production of Granulocyte-Macrophage Colony Stimulating Factor (GM-CSF) by cancer cells is correlated to host immune suppression and tumor metastasis, suggesting an immune evasion property of GM-CSF. Here we examined role(s) of recombinant GM-CSF in the regulation of NK-cell migratory properties in vitro. Methods: Previously published “Y” shape microfluidic platform was used to study the roles of GM-CSF gradient on NK-cell migrations. IL-2 activated human primary NK cells were used in the migration studies. Results: Our microfluidic-based migration study demonstrated a novel role of GM-CSF in regulating repulsive NK-cell migration under the stable GM-CSF gradient (at 20 ng/ml), followed by subsequent arrest in cell migration. Blocking of GM-CSF-Rα abolished the repulsive migratory behavior but not the arrest. In contrast, lower concentrations of GM-CSF induced hyper-polarization, immediate arrest of NK cells, and little/or no NK-cell migrations. Circularity measurement in controls and above experiments confirmed statistically the correlation between hyperpolarization and migration arrest. Future analyses will elucidate the mechanisms underlying the dual roles of GM-CSF in the regulation of NK-cell migratory properties.
The HMGB1-MD-2 axis as a novel therapeutic target in inflammatory diseases (CCR5P.210)
Authors: Yang Huan , Wang Haichao , Chavan Sangeeta , Billiar Timothy , Yousef Al-Abed , Tracey Kevin 
Published: January 2023

Abstract
Innate immune cells express receptors for pathogen-associated molecular patterns (PAMP e.g. LPS) as well as damage-associated molecular patterns (DAMP e.g. HMGB1), and orchestrate inflammatory responses to both infection and sterile injury. Secreted by activated immune cells or passively released by damaged cells, HMGB1 is subjected to redox modulation that distinctly influences its extracellular functions. Previously, it was unknown how the TLR4 signalosome distinguishes between HMGB1 isoforms. Here we demonstrate that the TLR4 adaptor molecule, myeloid differentiation factor 2 (MD-2), binds specifically to the cytokine-inducing disulfide HMGB1 isoform, to the exclusion of other isoforms. Screening of HMGB1 peptide libraries identified a tetramer (FSSE, designated as P5779) as a specific MD-2-antagonist preventing MD-2/HMGB1 interaction and subsequent TLR4 signaling mediating cytokine and chemokine release. Moreover, P5779 does not interfere with LPS-induced cytokine production, thereby preserving PAMP-mediated TLR4-MD2 responses. P5779 conferred protection in animal models of hepatic ischemia/reperfusion injury, chemical toxicity and sepsis. Taken together, these findings reveal a novel mechanism by which innate systems selectively recognize specific HMGB1 isoforms and suggest strategies to attenuate DAMP-mediated inflammatory responses while preserving anti-microbial immune responsiveness.
Glucosylceramide induced complement activation triggers inflammation in Gaucher disease (CCR5P.212)
Authors: Pandey Manoj , Tinch Stuart , Inskeep Venette , Zhang Wujuan , Setchell Kenneth , Köhl Jörg , Grabowski Gregory 
Published: January 2023

Abstract
Gaucher disease (GD) happens due to mutations in GBA1, which causes a deficiency of acid β-glucosidase critical for degradation of glucosylceramide (GC) into glucose and ceramide. Macrophages (Mɸs) were mainly having this defect and associated with eminent expression of cytokines, chemokines, and recruitment of activated immune cells in GD. The mechanism by which GC triggers such inflammation is still wanted. Excess of GC storage in dendritic and T cells has been reported to be the reason for their activation and production of inflammatory cytokines in Gba1 mouse model (D409V/null; 9V/null). Here, we have identified elevated expression of C5a and C5aR on 9V/null mice APCs. We therefore, hypothesized that GC induced C5a elicits immune inflammation in GD. To confirm this, conduritol B epoxide (CBE), induced chemical model of GD was developed in WT and C5aR-/- mice. We found that C5aR-/- mice were protected from CBE-induced GD development, which was associated with prolonged survival, marked reduction of GC, DCs and T cells positivity for CD40, CD80, CD86, CD40L, CD69, cytokines-chemokines secretion, immune cells recruitment, and decreased loss of red blood cells (RBCs) and platelets. Pharmacological blocking of C5aR in 9V/null mice showed marked reduction in several of these GD manifestations. Our data suggest that GC induced C5a contributes in disease development and targeting C5a signaling may have therapeutic potential for GD.
Determining the effect of BMP signaling on thymus fate specification and differentiation of the third pharyngeal pouch in the mouse. (HEM7P.235)
Authors: Frisbie Trent , O'Neil John , Gordon Julie , Vokes Steven , Richie Ellen , Manley Nancy 
Published: January 2023

Abstract
The third pharyngeal pouch is an endodermally derived epithelium that differentiates into thymus and parathyroid cells. Foxn1 (transcription factor) is a thymus-specific marker, which is required for thymic epithelial cell (TEC) proliferation and differentiation. Gcm2 is a parathyroid-specific marker, which is essential for parathyroid survival and differentiation. Loss of function genetic analysis of BMP4 showed that BMP4 is required for organ morphogenesis but not initial thymus fate; however, repression of BMP signaling by transgenic expression of ectopic Noggin inhibitor suppressed Foxn1expression. Based on these data, we hypothesize that BMP signaling is necessary for normal thymus fate specification during initial organogenesis with BMP signaling promoting thymus fate while inhibiting parathyroid fate. We are testing this hypothesis using inducible Gremlin transgenic mice in a tissue-specific Cre-Lox induction system, as well as gain and loss of function experiments in embryo cultures. Current data suggest delayed expression of Foxn1 when Gremlin is ectopically expressed. Explant cultures with dorsomorphin, a BMP inhibiting drug, showed a reduction of both Gcm2 and Foxn1. Also, cultured embryos with a BMP4 bead implant showed a reduction of Gcm2. Surprisingly, these data suggest inhibition of BMP signaling is suppressing Gcm2, while supporting the hypothesis that BMP signaling is necessary for initial thymus fate specification.
Prenatal and postnatal exposure to concentrated ambient particulate matter alters the developing immune system of mice (HEM8P.240)
Authors: Tijerina Pamella , Blum Jason , Hoffman Carol , Park Sung Hyun , Grunig Gabriele , Chen Lung-Chi , Zelikoff Judith 
Published: January 2023

Abstract
Prenatal exposure to certain air pollutants have been shown to cause immunological dysfunction in offspring, however previous experimental studies have yet to evaluate the vulnerability of the immune system throughout the pre- and early postnatal period. Therefore, to more accurately reflect human exposure, mice were exposed to concentrated fine-sized ambient particulate matter (PM2.5) both pre- and postnatally and parameters of immune status were assessed in offspring. Timed-pregnant dams were exposed 6hr/d throughout gestation (GD 0-17) to filtered air or PM2.5. At 5 wks-of-age, blood and spleen were collected from a subset of male and female offspring, and serum samples were analyzed for cytokine levels. Spleens were weighed and splenocytes isolated to assess changes in immune cell profiles by flow cytometry. Of the endpoints analyzed, only female offspring were significantly affected with pre- and postnatal PM2.5 exposure resulting in an 11% reduction of normalized splenic weight and decreased maturation status of splenic B cells (MHCII and CD45R expression) compared to their control counterparts. These sex-specific alterations demonstrate gaps in previous developmental studies that focused only on PM2.5-induced immune effects on male offspring. Together, these results suggest that particulate air pollution negatively impacts the developing immune system, proposing critical consequences for offspring exposed during the pre- and early postnatal period.
A role for Hox5 genes in T cell function during chronic allergic inflammation (HYP7P.268)
Authors: Ptaschinski Catherine , Hrycaj Steven , Wellik Deneen , Lukacs Nicholas 
Published: January 2023

Abstract
Allergic asthma is a significant health burden in western countries, and continues to increase in prevalence. T helper 2 (Th2) cells contribute to the development of disease through release of the cytokines interleukin (IL)-4, IL-5 and IL-13, resulting in increased airway eosinophils and mucus hypersecretion. While many factors are involved in the development of allergic asthma, the molecular mechanisms behind the disease remain largely unknown. As the three members of the Hox5 gene family (Hoxa5, Hoxb5 and Hoxc5) have been shown to play a role in lung development, we asked whether these genes also play a role in the adult lung in response to disease. We found that Hox5-deficient mice show exacerbated pathology compared to wild-type controls in a chronic allergen model, with an increased Th2 response as well as changes in lung tissue pathology. Examination of T cells from naïve wild-type or Hox5-deficient mice in Th2 polarizing conditions showed increased proliferation, enhanced Gata3 expression and production of IL-4, IL-5 and IL-13 in Hox5-deficient mice compared to wild-type controls. Overexpression of FLAG-tagged HOX5 proteins in Jurkat cells demonstrated HOX5 binding to the Gata3 locus, supporting a role for HOX5 proteins in direct transcriptional control of Th2 development. These results reveal a novel role for Hox5 genes as developmental regulators of immune cell function and Th2-induced pathology during allergic disease in the lung.
Regulation of allergic inflammation by murine endothelial cell transglutaminase 2 (HYP7P.260)
Authors: Soveg Frank , Abdala-Valencia Hiam , Campbell Jackson , Cook-Mills Joan 
Published: January 2023

Abstract
Tissue transglutaminase 2 (TG2) is a multifunctional enzyme that is involved in inflammatory processes. In allergic inflammation, previous research indicates that TG2 is upregulated in human asthma and in the lung endothelium of OVA-challenged mice. We hypothesized that endothelial cell TG2 is required for allergic inflammation. To test this hypothesis, we generated mice in which TG2 was specifically deleted in the endothelium using the Cre-Lox recombinase system. To induce allergic inflammation, mice were sensitized and challenged with OVA. Compared to wild type mice challenged with OVA, OVA-challenged TG2 knockout mice exhibited a significant reduction in lung airway resistance, the number of eosinophils in the BAL, and the number of eosinophils in the airway spaces. Endothelial deletion of TG2 did not affect chemokines and cytokines that regulate allergic inflammation. Taken together, these findings indicate that endothelial cell TG2 is required for allergic inflammation. This suggests that TG2 regulates the recruitment of eosinophils into OVA-challenged lungs. Future studies will focus on identifying mechanisms by which TG2 regulates signals for leukocyte recruitment during allergic lung inflammation.
Tim-3 promotes homeostasis of ulcerative colitis by inhibiting M1 macrophage polarization (INC6P.308)
Authors: Han Gencheng 
Published: January 2023

Abstract
Abstract We previously found that Tim-3 is involved in the physiopathology of inflammatory bowel diseases (IBD). However, the underlying mechanisms remain to be determined. Here we further demonstrated that Tim-3 contributes to the homeostasis of ulcerative colitis (UC), one type of IBD, by suppressing the polarization of pathogenic M1 macrophages. Downregulation or blockade of Tim-3 in UC is associated with biased pro-inflammatory macrophage (M1) response. Adoptive transfer of macrophages silenced of Tim-3 worsened colitis and enhanced inflammation. On the contrary, transgenic expression of Tim-3 attenuated DSS-induced colitis by down-regulating M1 macrophage response. Co-culture macrophages overexpressed of Tim-3 with intestinal lymphocytes decreased pro-inflammatory response. Tim-3 controls the activity of intestinal macrophages partially dependent on TLR-4 signaling, as in TLR-4 knockout mice blockade of Tim-3 pathway resulted in significantly attenuated colitis and decreased M1 macrophage response. Finally we demonstrated that Tim-3 signaling inhibited the phosphorylation of IRF3, a transcriptional factor regulating macrophages polarization. A better understanding of this pathway may shed new light on the pathogenesis of UC and help to find new therapeutic strategy.
LPS-induced p21 is required for M2 polarization of endotoxin- tolerant macrophages and controls the accumulation of inhibitory p50/p50 NF-κB (INC6P.317)
Authors: Rackov Gorjana , Martínez-A Carlos , Balomenos Dimitrios 
Published: January 2023

Abstract
Gram-negative bacterial infection can lead to systemic inflammation and sepsis — a complex pathology that is the third leading cause of death in the U.S. A critical mechanism in lowering inflammation and septic shock is endotoxin tolerance, a state of hyporesponsiveness to secondary lipopolysaccharide (LPS) challenge. p21 controls macrophage activation independently of its cell cycle inhibitor activity. Here, we investigated M1 to M2 macrophage polarization during endotoxin tolerance, which is regulated by NF-κB composition switch from p65/p50 to p50/p50. p21 deficiency led to delayed formation of inhibitory p50/p50 NF-κB homodimers that control IFN-β promoter, a key cytokine which orchestrates M1 responses. Consequently, lack of p21 enhanced IFN-β production and IFN-β-dependent STAT1 phosphorylation, resulting in upregulation of iNOS and M1 chemokines. Importantly, p21-deficient macrophages had impaired ability to acquire M2-like LPS-tolerant profile, showing reduced induction of M2 genes such as arginase I. The biological significance of our work was reflected in an in vivo model of endotoxin tolerance, where p21-deficient mice failed to develop tolerance and showed high M1-dependent responses and death. Overall, we identified p21 as a key molecule that regulates M2 polarization and endotoxin tolerance, through NF-κB composition switch from p65/p50 to p50/p50. Thus, analysis of the role of p21 in macrophages may be of therapeutic value for optimizing M1/M2 ratio in disease.
TLR stimulation of type II NKT cells requires cell to cell contact with DCs with involvement of CD40-CD40L and IL-12p40 (INC6P.318)
Authors: Tripathi Prabhanshu , Sedimbi Saikiran , Karlsson Mikael , Yrlid Ulf , Kadri Nadir , Cardell Susanna 
Published: January 2023

Abstract
Natural killer T (NKT) cells are CD1d restricted innate like lymphocytes recognizing lipid antigens and mediating immune regulatory functions. NKT cells are divided into two subsets based on the type of T cell receptor (TCR) expressed. Type 1 or invariant NKT cells uses an invariant TCRα-chain (Vα14-Jα18 in mice/Vα24-Jα18 in humans) and type II or diverse NKT cells are all non Vα14 expressing NKT cells. Most of the knowledge about NKT cells have been derived from type I NKT cells, while type II NKT cells are less well explored. Here, we investigated the signals driving Toll-like receptor (TLR) ligand activation of type II NKT cells. We use the 24αβ mouse model expressing a transgenic Vα3.2 and Vβ9 type II NKT cell TCR on the C57/BL6 background. Using in vitro co-culture experiments with 24αβ type II NKT cells and FLT3L derived bone marrow dendritic cells (BMDCs) and TLR ligands, we have analyzed the factors required for type II NKT cell activation, applying BMDCs from different knock out mice. TLR stimulated DCs potently activated type II NKT cells to secrete IFN-γ in a CD1d and type I IFN independent manner. In contrast, an absolute requirement of IL12p40 and partial dependence on CD40, IL15 and IL18 for optimal IFN-γ induction was observed. Thus, our data suggest that TLR ligand - BMDC mediated activation of type II NKT cells requires cell - cell contact that includes CD40 - CD40L ligation, IL15, IL18 and IL-12, but not CD1d - TCR interaction.
Interleukin 4 induces a unique NK cell population in vivo and in vitro (INC6P.325)
Authors: Tsuyoshi Kiniwa , Yutaka Enomoto , Ai Omi , Atsushi Miyajima 
Published: January 2023

Abstract
NK cells are cytolytic and cytokine-producing effector cells that play major roles for clearance of tumors and virus-infected cells. NK cells are known to be activated by IL-12, a Th1-type cytokine, and secrete a large amount of IFN-γ that accelerates Th1-type responses. However, the roles of NK cells in Th2-type responses are largely unknown. As IL-4 acts as an initiator of Th2-type responses, we examined the phenotype of NK cells in mice over-expressing IL-4 by hydrodynamic tail vein injection. IL-4 expression induced a unique NK cell population (NK1.1high/CD11blow/IL-18Ralow), which was different from conventional mature NK cells (NK1.1high/CD11bhigh/IL-18Rahigh). Interestingly, over-expression of IL-13, whose biological activities largely overlap with IL-4, failed to induce this population. Moreover, these IL-4-responsive NK cells produced a large amount of IFN-γ in response to IL-12 and exhibited a high cytotoxicity compared to conventional mature NK cells. We also found that incubation of conventional mature NK cells with IL-15 and IL-4 changed their phenotype to that similar to IL-4-responsive NK cells, i.e., they became IL-18Ralow and secreted a large amount of IFN-γ in response to IL-12, and produced cytotoxic granules without additional stimulation. Collectively these results suggested that IL-4 induces a unique NK cell population with strong NK activity independent of IL-13 and that IL-4 has a specific role in Th2 responses through this IL-4-responsive NK cells.
Extracellular superoxide dismutase promotes immature neutrophil egress from the bone marrow (INC6P.303)
Authors: Witter Alexandra , Break Timothy , Indramohan Mohanalaxmi , Mummert Mark , Berg Rance 
Published: January 2023

Abstract
Extracellular superoxide dismutase (ecSOD) regulates extracellular concentrations of reactive oxygen species (ROS) to protect tissues during infection and inflammation. Using three groups of mice with varying levels of ecSOD activity, we have previously shown that ecSOD activity enhances neutrophil recruitment to the liver, yet inhibits the innate immune response against Listeria monocytogenes (LM) leading to increased host susceptibility. However, it is unclear whether ecSOD activity affects neutrophil recruitment and function in a cell-intrinsic manner or by modulating the extracellular environment. Using adoptive transfer experiments, we observed that ecSOD activity does not affect neutrophil recruitment or function in a cell-intrinsic manner. Additionally, we determined that ecSOD activity protects the extracellular matrix (ECM) and leads to an increase in phenotypically immature neutrophils in the bone marrow and liver. Collectively, our data suggest that ecSOD activity inhibits degradation of the ECM and promotes egress of immature neutrophils out of the bone marrow and into the liver where they provide inadequate protection against LM. These studies highlight the potential therapeutic value of ecSOD inhibitors to enhance immune responses during bacterial infections.