bluuebunny/crossref_metadata_2025_split huggingface dataset:
The T cell receptor alpha/delta locus adopts distinct contracted conformations during primary and secondary T cell receptor α rearrangement (HEM2P.242)
Authors: Carico Zachary , Krangel Michael 
Published: January 2023

Abstract
In DP thymocytes, primary TCRα rearrangements are restricted to proximal Vα segments at the 3’ end of the Tcra/d locus. We have shown that this restricted Vα usage is supported by a 3’ contracted and 5’ decontracted conformation of Tcra/d. Secondary rearrangement, however, generates a far more diverse pool of Vα-Jα pairings. To investigate the structure the 5’ end of the locus might adopt after primary rearrangement, we performed 3D-FISH on Tcra/d alleles engineered to mimic a natural TRAV17-TRAJ57 rearrangement. We found that the artificially rearranged Tcra/d alleles were markedly contracted at the 5’ end relative to unrearranged Tcra/d. Notably, we observed a similar 5’ end contraction of the locus in CTCF-deficient DP thymocytes with unrearranged Tcra/d. This led us to hypothesize that loss of a critical CTCF binding site as a result of primary rearrangement might promote the 5’ end contraction. Knockout of the T early alpha promoter (TEA), but not other CTCF-bound elements in the region deleted by primary rearrangement, resulted in 5’ contraction of Tcra/d. These data suggest that diversity in secondary TCRα rearrangements is supported by contraction of the whole length of Tcra/d, and that CTCF binding by TEA plays a critical role in enforcing a 5’ decontracted conformation for primary rearrangement. Using 4C, we are now working to understand specific changes in long-range DNA contacts between pre- and post-rearrangement alleles.
IL10 mediates the protective effect of voluntary exercise on stroke-induced injury (HUM1P.255)
Authors: Selvaraj Uma Maheswari , Poinsatte Katherine , Ortega Sterling , kong xiangmei , Plautz Erik , Noorbhai Ibrahim , Stowe Ann 
Published: January 2023

Abstract
Previous data show that voluntary exercise prior to stroke reduces neuronal injury in wild type (WT) mice. Our lab found that exercise specifically modulates B cells to upregulate IL10, which could reduce post-stroke inflammation. To determine the influence of IL10 on exercise-mediated neuroprotection, IL-10-null mice (male, 12-16 weeks old) were randomly separated into sedentary and voluntary exercise (3 weeks on monitored running wheels) groups. Both groups were subjected to a 60 minute transient middle cerebral artery occlusion, with infarct volumes and splenic immune populations assessed 24 hours after stroke by a blinded observer. Voluntary exercise (n=11) did not reduce infarct volume compared to sedentary mice (n=8) in the absence of IL-10. Exercise increased B2 cell (CD1d-CD5-; p&lt;0.05) and B regulatory (Breg) cell (CD1d+CD5+; p=0.08) populations in the spleen. Mice with the highest exercise intensity exhibited both the lowest splenic Breg populations (p&lt;0.05) and the lowest infarct volumes (p=0.09). This would suggest an IL10-independent mobilization of Bregs by exercise prior to stroke, though future studies should determine if this neuroprotective Breg population moves into the ischemic brain to reduce neuronal injury.
Alarmin HNPs 1-3 predicts theonset of lung injury after cardiac surgery in children (HUM1P.259)
Authors: Liu XiWang , Chen QiXing , Lai Dengming , Qin ChaoJin , Fang XiangMing , Shu Qiang 
Published: January 2023

Abstract
Introduction:Human neutrophil peptides (HNPs) 1-3 are endogenous mediators to be characterized as alarmins. Methods:Children younger than 3 years after cardiac surgery were prospectively enrolled. Plasma concentrations of HNPs 1-3 and inflammatory cytokines were measured by ELISA during and after operation. Results: Thirty patients were enrolled which included 18 (60%) infants. Plasma HNPs 1-3 and the pro-inflammatory cytokine IL-6 levels significantly increased immediately after CPB (P &lt; 0.001), while IL-8 increased 1 hour after operation (P = 0.002). The anti-inflammatory cytokine IL-10 levels immediately after CPB were also significantly elevated compared with baseline (P &lt; 0.001). The multiple linear regression analysis showed that the plasma HNPs 1-3 levels immediately after CPB was independent correlated with declined lung function, as reflect by the PaO2/FiO2 ratio on the first 2 days after operation (for the first day: OR, -1.067, 95% CI, -0.548 to -1.574; P &lt; 0.001; for the second day: OR, -0.667, 95% CI, -0.183 to -1.148; P = 0.009) and prolonged mechanical ventilation time (OR, -0.039, 95% CI, -0.005 to -0.056; P = 0.022). Plasma levels of HNPs 1-3, IL-8 and IL-10 returned to normal values, while IL-6 levels remained significantly higher than baseline 24 hours after operation (P &lt; 0.001). Conclusions: Elevated HNPs 1-3 levels correlate with impaired lung function, and HNPs 1-3 is a useful early alarmin biomarker for lung injury inchildren after cardiac surgery.
Inhibition of fatty acid oxidation blocks asthma in mice (HYP2P.340)
Authors: Al-Khami Amir , Ghonim Mohamed , Pyakurel Kusma , Ibba Salome , Trillo-Tinoco Jimena , Hossain Fokhrul , Del Valle Luis , Rodriguez Paulo , Boulares Hamid , Ochoa Augusto 
Published: January 2023

Abstract
Background: There has been a growing appreciation for the role of energy metabolic pathways in the differentiation and function of immune cells. Unpublished findings from our laboratory suggest that inhibiting fatty acid oxidation (FAO) modulates the activation and function of tumor-infiltrating myeloid cells, indicating a potentially important role for FAO in inflammation and thus inflammatory diseases such as asthma. Objective: We sought to test the hypothesis that FAO plays an important role in asthma manifestation. Methods: Etomoxir, an inhibitor of the FAO rate-limiting enzyme carnithine palmitoyltransferase-1, was used to test our hypothesis in an ovalbumin-based murine model of asthma. Results: Etomoxir treatment thirty minutes after ovalbumin challenge resulted in a significant reduction in the recruitment of eosinophils and macrophages into the lungs without a prominent effect on the total number of lymphocytes. Etomoxir treatment also prevented ovalbumin-induced hyperresponsiveness. The protective effects of etomoxir were associated with a decrease in Th2 cytokines and ovalbumin-specific IgE production. Additionally, the frequency of splenic macrophages was lower in etomoxir-treated mice, compared with control. Conclusions: Our preliminary data suggest the inhibition of FAO as a likely strategy to block asthma traits. As such, we are currently uncovering the mechanisms by which FAO inhibition reduces the pathogenesis of asthma.
ICOS: ICOS-ligand interaction is essential for ILC2 function and survival (HYP2P.322)
Authors: Maazi Hadi , Patel Nisheel , Sankaranarayanan Ishwarya , Riagas Diamanda , Soroosh Pejman , Freeman Gordon , Sharpe Arlene , Akbari Omid 
Published: January 2023

Abstract
Type 2 Innate lymphoid cells (ILC2s) are a newly identified subset of immune cells that play important roles in the pathogenesis of allergic asthma by producing large amounts of IL-5 and IL-13. ILC2 lack lineage markers but express CD45, IL-2Rα, IL-33R and IL-7Rα. All murine ILC2s and a significant portion of human ILC2s express Inducible T-cell COStimulator (ICOS) that is essential for T cell activation and function, however, the role of ICOS in ILC2s remains unknown. We investigated the role of ICOS in the function and survival of murine and human ILC2s using ICOS-/- and RAG2-/- and humanized mice in different experimental setups. We found that:1) ICOS-/- mice show lower IL-33-induced airway hyperreactivity (AHR) and eosinophilia than wild type (WT) mice. 2) Survival and the number of ILC2s is substantially lower in ICOS-/- than WT mice. 3) Blocking anti-ICOS antibody reduces survival and the number of ILC2s in WT mice. 4) Ex vivo stimulated ICOS-/- ILC2s show impaired IL-5 and IL-13 production compared to WT ILC2s. 5) Human peripheral ILC2s express ICOS and blocking ICOS:ICOS-Ligand interaction impairs their IL-5 and IL-13 production in vitro and IL-33 induced AHR and eosinophilia in humanized mice. 6) Human and murine ILC2s express ICOS-Ligand. 7) ICOS signaling modulates STAT5 pathway. Our results indicate that ICOS is required for the optimal function and survival of ILC2s and can be a novel therapeutic target in patients with ILC2-mediated asthma and lung inflammation.
Cell membrane stabilization prevents the natural IgM-mediated complement response to hypoxia in human coronary artery endothelial cell (INC1P.359)
Authors: Zhang Ming , Lee Haekyung 
Published: January 2023

Abstract
Hypoxia occurs in many clinical conditions, including ischemic diseases (e.g. heart attack, cerebral stroke and pulmonary hypertension), surgery (e.g. organ transplantation) and trauma. The goals of this study were to determine whether natural IgM-mediated complement activation occurs during hypoxia of human tissue prior to reoxygenation and whether pre-incubation with the sugar trehalose, a membrane stabilizer, can prevent hypoxia-related injury. Primary human coronary artery endothelial cells (hCAECs) were used in two in vitro hypoxia models. Subjection of hCAECs to hypoxia, without subsequent reoxygenation, was found to produce IgM deposition and C3 activation and deposition. Trehalose blocked these effects, indicating that cell membrane instability due to hypoxia is upstream of natural IgM-mediated complement activation. The results indicate that trehalose has potential as a therapeutic intervention in hypoxia-related tissue injury.
Hepatitis C virus-infected Huh7.5 cell reduces NK cell functions via HCV’s serine protease NS3/4A (INC2P.408)
Authors: Yang Chang Mo , Park Jeon Han , Lee Jae Myun 
Published: January 2023

Abstract
Hepatitis C virus (HCV) infection is characterized by high frequency of chronic cases and impairment of innate and adaptive immune responses are the causes. Innate immune response impairment may involve modulating NK cell functions. However, NK cell functions’ impairment mechanism in the early phase of HCV infection and viral proteins’ roles are controversial. Therefore, we investigated which protein of HCV modulates NK cell functions. Human hepatoma Huh7.5 cells were infected with cell culture-generated HCV virions and cocultured with ex vivo NK cell. Cell-to-cell contact between NK cell and infected cells significantly reduced NK cell’s natural cytotoxicity and IFN-γ production. We also assessed effects on NK cell functions using HCV’s replicon cells. These replicon cells affected NK cell functions’ reduction. Whereas, we observed the restoration of NK cell functions when contacted with infected Huh7.5 cells, which were treated with HCV NS3/4A serine protease inhibitor, BILN-2061. The capacity of NK cell to degranulation against K562 and IFN-γ production level was increased significantly compare to infected Huh7.5 cells. These restored functions of the NK cell, correlated with some activating receptors expressed on NK cell surface, especially NKp46 expression level. Our observations suggest that HCV’s serine protease role in NS3/4A protein responsible for abrogation of the NK cell functions in the early phase of infection through downregulation of NKp46 receptor on NK cell.
Involvement of IL-1β on cognitive impairment after experimental pneumococcal meningitis. (INM1P.432)
Authors: Barichello Tatiana , Generoso Jaqueline , Simoes Lutiana , Ceretta Renan , Dominguini Diogo , Carvalho Vilela Márcia , Comim Clarissa , Lucio Teixeira Antonio , Quevedo Joao 
Published: January 2023

Abstract
Pneumococcal meningitis is associated with high rates of mortality and long-term cognitive impairment. In the current study, we evaluated the effects of an interleukin (IL)-1β receptor antagonist (IL-1Ra) on memory, cytokine, and BDNF levels in experimental pneumococcal meningitis. Adult Wistar rats were divided into four groups: control/saline, control treated with IL-1Ra, meningitis/saline and meningitis treated with IL-1Ra. The animals were killed at 24 h post-infection. In the meningitis/saline group IL-1β and CINC-1 levels increased at 24 h post-infection; however, treatment with IL-1Ra reversed these increases in the hippocampus. In a second experiment, the rats received antibiotic and were subjected to behavioural tasks (open field, step-down inhibitory avoidance and object recognition), cytokine and BDNF levels ten days after meningitis induction. In the open-field task, the meningitis group did not exhibit differences in motor and exploratory activity, indicating habituation memory impairment. The same impairment occurred in the novel object recognition memory and step-down inhibitory avoidance task (aversive memory) in the meningitis group; however, adjuvant treatment with IL-1Ra prevented memory impairment. The IL-4, IL-6, IL-10 and BDNF levels were increased in the meningitis/saline and meningitis/IL-1Ra groups. These findings illustrate a neuroprotective role of IL-1Ra inhibitor and the involvement of IL-1β on cognitive impairment after pneumococcal meningitis.
In vivo plasma LPS levels in HIV negative subjects alter T cell proliferative responses, stimulate cytokine release and induce TLR cross tolerance in monocytes ex vivo (IRC4P.604)
Authors: Palmer Christine , Romero-Tejeda Marisol , Sirignano Michael , Sharma Siddhartha , Allen Todd , Altfeld Marcus , Jost Stephanie 
Published: January 2023

Abstract
Multiple studies have shown correlates of immune activation with microbial translocation and plasma lipopolysaccharide (LPS) levels during HIV-1 infection. It is unclear whether this activation is solely due to LPS, residual viral replication, or both. LPS and other pathogen-associated molecular patterns (PAMPs) are recognized by Toll-like receptors (TLRs). Binding of PAMPs to TLRs can alter subsequent responses by inducing self/cross-tolerance or priming. These effects of can alter immune functions in the context of chronic LPS exposure. Few studies have addressed the effects of chronic in vivo levels of LPS on specific immune functions in humans in the absence of chronic viral infection. We previously reported on a cohort of HIV negative high-risk men who have sex with men with elevated plasma LPS levels. This cohort allowed us to assess cellular immune functions in the context of plasma LPS levels ex vivo without confounding viral effects. Using 2 time points with different plasma LPS levels, we now show that in vivo plasma LPS levels altered ex vivo cytokine expression by monocytes, without stimulation and in response to several TLR ligands. We further showed that high levels of plasma LPS in vivo delayed early T cell proliferative responses in vitro, whereas intermediate plasma LPS levels enhanced T cell proliferation. These data suggest that increased levels of plasma endotoxemia can have profound effects on immune function.
IL-10 inducing bacteria are preferentially depleted in the gut of HIV infected subjects (IRC4P.607)
Authors: Neff Charles , Rhodes Matthew , Donnelly Jody , Schneider Jennifer , Mazmanian Sarkis , Lozupone Catherine , Palmer Brent 
Published: January 2023

Abstract
Chronic HIV infection is associated with a dramatic change in gut microbiota composition, characterized by a drop in the Bacteroides genus and increase in Prevotella genus. Bacteroides fragilis, which is depleted during HIV infection, interacts with CD4+ T cells and induces IL-10 producing T regulatory cells (Tregs) using polysaccharide A (PSA). We hypothesize that massive depletion of CD4+ T cells during HIV infection results in the inability of B. fragilis to induced IL-10 producing T regulatory cells and persist in the gut. To characterize whether other bacteria depleted during HIV infection also produce PSA we screened genomes of bacteria for the presence of close homologues to essential genes in the PSA operon. Genome screening for PSA-like gene elements showed that many of the species of bacteria predicted to encode for PSA decreased with HIV infection. Stimulation of PBMC and Lamina Propria Mononuclear Cells (LPMC) with these bacteria demonstrated that compared to non-predicted PSA producers, PSA producing bacteria induced more Tregs and higher levels of IL-10. These data suggest that the compositional changes seen in HIV infection may be in part a result of the inability of PSA producing bacteria to stimulate IL-10 producing Tregs critical for damping innate immune responses and allowing colonization. The loss of these IL-10 inducing gut bacteria may also contribute to the generalized inflammatory state and chronic immune activation seen in HIV infected subjects.
Glutamate ionotropic receptor (NMDAR) modulates T cell survival (IRM7P.712)
Authors: Peron Jean Pierre , Brandão Wesley Nogueira , Rossato Cristiano , Camara Niels Olsen 
Published: January 2023

Abstract
Introduction: T cells play a crucial role in adaptive immune responses and neuroinflammatory diseases such as multiple sclerosis. Glutamate is one of the most abundant neurotransmitter in the central nervous system; it can acts through two different receptor families: metabotropic and ionotropic. It has been demonstrated that T cells can be the target of glutamate during antigen presentation and immunological synapses, however, little is known about its role on T cell survival. Methods and Results: To evaluate whether NMDAr ligands exert a role in T cell survival, we harvested spleen cells from C57BL/6 female mice and cultivated in the presence of anti-CD3 (1µg/mL) in vitro for 5 days. On day 5, cells were stained for CD4+/CD8+ and 7-AAD and data were acquired by flow cytometric analysis. NMDAr blockage by MK801 induced cell death while NMDA agonist did not affect T proliferation and T cell numbers. Conclusion: Our data demonstrate that NMDAr exert a crucial role in T cell survival. These findings not only contribute to the advantage of the neuroimmunology field but also suggest that T cells which infiltrate the central nervous system could be target of the neurotransmitter glutamate via NMDAr in neuroinflammatory diseases.
Novel interactions between IL17 and IFNγ signaling mediate native host defense to Staphylococcus (MPF2P.753)
Authors: Barin Jobert , Talor Monica , Gebremariam Elizabeth , Schaub Julie , Miller Lloyd , Rose Noel , Cihakova Daniela 
Published: January 2023

Abstract
In these studies, we characterize a novel spontaneous inflammatory disease that develops in the concurrent absence of the shared IL17 receptor subunit IL17RA, and the receptor for IFNγ. As part of previously published studies on convergent signaling between IFNγ and IL17, we generated double-knockout mice, deficient in both IL17RA and IFNγ. We observed large purulent abscesses developing in the IL17RA-/-IFNγRI-/- double-knockout strain, but neither of the parental single-knockout controls. Chronic mucocutaneous abscesses developed spontaneously in both sexes, in the buccal mucosa and the skin of the forelimb, and were found to contain uncontrolled Staphylococcal outgrowth. Histopathologic examination of the oral abscesses and flow cytometric enumeration of these tissues demonstrated extensive neutrophilic infiltration of the surrounding tissues. Interrogation of circulating immunoglobulins revealed elevated serum IgE in IL17RA-/-IFNγRI-/- double-knockout animals, positioning their disease as a novel model of features of Hyper IgE syndrome (Job’s syndrome).
The role of B cell-intrinsic gp96 /grp94 in sepsis (MPF2P.747)
Authors: Liu Bei , Fan Hongkuan 
Published: January 2023

Abstract
gp96, also known as grp94, is a master protein chaperone for Toll-like receptors (TLRs) and integrins in the endoplasmic reticulum (ER) and plays critical roles in innate immunity. However, the role of B cell-intrinsic gp96 in sepsis has not been studied. Sepsis is a clinical syndrome caused by a severe immune response to infection. B cell has been implicated in protecting against bacterial sepsis. We addressed this question using a unique B cell specific gp96 knockout mouse model. KO mice do develop mature and functional B cells, in spite of defects of gp96 null B cells in integrin-dependent migration and failure to proliferate in response to multiple TLR ligands such as Pam3 and LPS. We challenged WT and KO mice with a lethal dose of LPS, and we found that WT mice produced significantly more serum TNF-α, IL-6 and IL-12 than did KO mice. Consistent with the detrimental effect of these cytokines in sepsis, we found that the WT mice were more susceptible to LPS-induced sepsis than the KO mice. By day 2, 100% WT mice succumbed to endotoxemia. In contrast, 40% of KO mice survived to the same dose of LPS challenge. In addition, using a well-defined sepsis model of cecal ligation and puncture (CLP), we demonstrated that KO mice were unable to mount effective response against polymicrobial sepsis, underscoring the importance of B cells in innate immunity. This study indicates that B cell-intrinsic TLR signaling contributes to sepsis-induced B cell activation and outcome of sepsis.
Altered gastrointestinal environment and immune cellular plasticity during disease progression of type 1 diabetes (MUC2P.931)
Authors: Wallet Shannon , Hulme Maigan , Nelson Michael , Graves Christina , Amador Byron , Sorenson Heather , Brusko Todd 
Published: January 2023

Abstract
The gastrointestinal (GI) tract is the largest environmental interface which is a barrier to environmental insults and a site of immune activation and tolerance induction. The initiating events leading to the loss of self-tolerance which results in the autoimmune process of type1 diabetes (T1D) have yet to be fully defined. Leakiness at the GI barrier has been observed preceding symptomatic onset of T1D. Using the non-obese diabetic (NOD) mouse, we assessed measures of barrier integrity, global intestinal inflammation, as well as the frequency of gastrointestinal and pancreatic innate lymphoid (ILC), regulatory and inflammatory cell subsets at key checkpoints of disease to determine kinetics associated with the loss of tolerance. Early in the disease process, NOD mice exhibited minor losses in barrier function along with elevated levels of duodenal TNFα and IFNɣ. Concomitant with an increased frequency of inflammatory T cells and reduced frequency of regulatory T cells, NOD mice also presented with an increased frequency of type 3 ILCs and a decreased frequency of type 1 ILCs within the mesenteric lymph node (MLN) at all stages of disease and in the pancreatic lymph node (PLN) at 8 wks of age. Overall, these data support a model wherein early in disease, minor changes in barrier function can result in intestinal inflammation shifting the balance of immunoregulation to that of inflammation potentially resulting in the loss of self-tolerance responsible for T1D.