bluuebunny/crossref_metadata_2025_split huggingface dataset:
A mouse model of T cell dysfunction in chronic Hepatitis B (105.24)
Authors: Tao Mi-Hua , Huang Ya-Hui , Chou Ho-Yuan , Fang Cheng-Chieh 
Published: January 2023

Abstract
The virus-host interactions responsible for dysfunctions of hepatitis B virus (HBV)-specific T cells and the subsequent development of severe liver diseases are poorly understood. Mice are not naturally infected by HBV, presumably due to a lack of HBV receptors on mouse hepatocytes. To bypass this entry step of HBV infection, we used adeno-associated viral vectors to introduce the HBV genome (AAV/HBV) into the liver of immunocompetent mice. We confirmed the presence of HBV virions and proteins in the serum and liver of all AAV/HBV-transduced mice. These mice were negative for HBV surface (HBs) and e protein (HBe)-specific Abs, but positive for HBV core (HBc)-specific Ab, a profile similar to that observed in chronic HBV patients. AAV/HBV transduction induced HBs- but not HBc-specific IFN-γ-producing CD8+ T cells, preferentially enriched in the liver. The number of HBs-reacting CD8+ T cells decreased with time and their effector functions were severely impaired as suggested by their failure to respond to HBs immunization. Interestingly, PD1 expression on hepatic CD8+ T cells increased gradually after AAV/HBV transduction, suggesting an important role of PD-1 in constraining T cell activity and maintaining HBV chronicity. Nevertheless, six months after transduction these AAV/HBV-transduced mice manifested evidence of hepatic inflammation and regeneration. Our AAV/HBV-transduced murine model is a unique instrument for studying the immunological events in human chronic HBV.
Genetic similarities and differences in the anti-HIV-1 Env antibody responses between humans and rhesus macaques (105.40)
Authors: Guan Yongjun , Sajadi Mohammad , Robinson James , Reid William , Lewis Roberta , Gorny Miroslaw , DeVico Anthony , Lewis George 
Published: January 2023

Abstract
We previously described a method for rapid cloning human monoclonal antibody (mAb) from memory B cell (Bmem). Here, we have put this method in practice for isolating a large panel of mAbs against HIV-1 envelope (Env) protein and have extended it as a general strategy to isolate monkey mAbs against HIV-1 Env from Bmem of a SHIV infected rhesus macaque. Ninety-six new mAbs were cloned from 5 HIV-1 infected humans, of which 64 are clonally unique Env mAbs. Thirty-five mAbs against HIV-1 Env were cloned directly from Bmem or from immortalized Env B cell lines both derived from SHIV infected rhesus macaques. Genetic analyses showed that humans and rhesus macaques can use similar VH genes for generating Abs against similar Env epitopes. For example, they both can use VH1-69, VH1-24 and VH2-70 genes for mAbs against CD4 induced (CD4i) Env epitopes, and use VH5-51 gene for V3 mAbs. However, the strong bias usage of VH1-69 gene for human CD4i Abs was not seen in rhesus macaques. In addition, the biased usage of kappa gene for anti-Env Abs in HIV-1 infected people was not seen in rhesus macaques. Instead, SHIV infected rhesus macaques tends to use lamda light chain gene to encode mAbs against the HIV-1 Env protein. This information on the similarities and differences of anti-Env Ab responses between human and rhesus macaques should help to more judiciously employ the non-human primates model to advance HIV vaccine candidates into clinical trials.
T cell epitopes were identified in HTNV structural protein (105.9)
Authors: Jin Boquan , Ma Ying , Wang Jiuping , Zhuang Ran , Wang Meiliang , Xu Zhuwei , Yi Jing , Yan Guolin , Zhang Yusi 
Published: January 2023

Abstract
Objectives: To investigate the cellular immune response to Hantaan virus (HTNV) infection by identifying T cell epitopes of HTNV structural protein (nucleoprotein, NP and glycoprotein, Gn/Gc) and their HLA-restriction. Methods: The HLA-restriction of HTNV-NP T cell epitopes were identified by determining T cell response to peptide-loaded B lymphoblastoid cell lines which were HLA partially matched. T cell responses to an array of overlapping peptides derived from HTNV-Gn/Gc was quantitated by ex vivo IFN-γ ELISPOT analysis. Results: In the HTNV-NP, one HLA-A*02-, one HLA-B*07-, one HLA-A*11-, two HLA-A*33-, and three HLA-B*35-restricted T cell epitopes were identified. 86.6% hemorrhagic fever with renal syndrome (HFRS) patients (71/82) showed T cell response to 61.9% HTNV-Gn/Gc 15-mer peptides (174/281), in which, 11 potential dominant epitopes were screened out. Moreover, the response frequencies of HTNV-Gn/Gc-specific T cells at the earliest available time point were significantly higher in patients who had mild or moderate HFRS than in those who had severe or critical HFRS (P=0.007), suggesting that T cell response to these epitopes may affect HFRS disease progression in patients. Conclusion: T cell immunty plays a role in immunoprotection upon HTNV infection. Identification of T cell epitopes of HTNV structural protein and their HLA restriction may advance our understanding of immunoprotection and/or pathogenesis of HFRS, thereby improve the design of novel HTNV vaccine.
Enhanced in vivo immunity and protection provided by cationic lipid-DNA complex adjuvanted influenza vaccination is independent of Toll-like receptor 9 (106.16)
Authors: Botham Crystal , Hong David , Giffon Thierry , Draghi Monia , Fairman Jeff , Lewis David 
Published: January 2023

Abstract
As current licensed influenza vaccines provide little or no cross-protective immunity, we have pursued using cationic lipid-DNA complex (CLDC) adjuvant to boost adaptive immunity to inactivated influenza vaccines. CLDC consists of a non-coding plasmid DNA, rich in immunostimulatory CpG motifs, which is encapsulated in cationic lipids. Previous murine and non-human primate studies showed that CLDC adjuvanted influenza vaccination induced more robust immunity and cross-protection. We hypothesized that the CLDC plasmid mediates these effects, at least in part, in a TLR9-dependent manner. Bone-marrow derived dendritic cells (BMDCs) incubated in vitro with CLDC secreted high levels of interferon-alpha (IFN-α), and this induction required CLDC’s DNA component. CLDC-induced IFN-α expression was significantly reduced using TLR9-/- BMDCs. We next vaccinated wildtype and TLR9-/- mice with CLDC-adjuvanted inactivated influenza vaccines. Surprisingly, CLDC’s immunostimulatory responses in vivo were TLR9-independent in that there was no significant difference between wildtype and knockouts for either vaccine immunogenicity (influenza-specific antibody and T-cell responses) or for cross-protection after viral challenge. These studies suggest that the DNA moiety of CLDC enhances immune responses in vivo by a novel, TLR9-independent mechanism. Determining this mechanism will likely be important in the optimal application of CLDC as an adjuvant to human vaccination.
Colonization factor antigen I expression by Salmonella induces CREB-dependent stimulation of CD39+CD4+ T cells responsible for protection against collagen-induced arthritis (107.5)
Authors: Kochetkova Irina , Thornburg Theresa , Callis Gayle , Pascual David 
Published: January 2023

Abstract
Salmonella vaccine vector expressing enterotoxigenic E. coli CFA/I fimbriae has been shown to protect against EAE and CIA. Vaccine-induced CD25+CD4+ and CD25-CD4+ T cells were potent against CIA, and such protection was reversed by anti-TGF-β treatment. We demonstrate, Salmonella-CFA/I-stimulated CD39+CD4+ T cells correlate with accelerated hydrolysis of extracellular ATP, a mechanism of immune suppression. Since vaccine-induced FoxP3-CD39+CD25-CD4+ T cells are shown to be the source of TGF-β, we hypothesized TGF-β could be important in regulating CD39 expression and consequential suppression of CIA. Salmonella-CFA/I-induced CD4+ T cells featured enhanced activation of cAMP-response element-binding protein (CREB), essential for transcriptional regulation of CD39. CREB phosphorylation was suppressed by in vivo treatment of Salmonella-CFA/I-immunized mice with anti-TGF-β mAb. Decrease in phosphorylated CREB correlated with 2-fold less CD39+CD4+ T cells. Although Salmonella-CFA/I-induced FoxP3-CD4+ T cells protected against CIA, as well as CD39+CD4+ T cells upon adoptive transfer, subsequent FACS analysis of recipients’ CD4+ T cells revealed conversion of FoxP3-(GFP-) cells to FoxP3+. Thus, Salmonella-CFA/I stimulates TGF-β production by FoxP3-CD39+CD4+ T cells, promoting the CREB-dependent expansion of CD39+CD4+ T cells becoming regulatory FoxP3+CD4+ T cells. Supported by AT004312.
The characterization of thymus-derived natural Th17 cells and their response to inflammation. (108.9)
Authors: Nowyhed Heba , Bertino Sarah , Tao Jian , Marks Benjamin , Choi Jin-young , Craft Joseph 
Published: January 2023

Abstract
CD4 T helper (Th) cells that secrete interleukin (IL)-17 (Th17) complement the function of Th1 and Th2 cells as a third effector lineage, with a distinct role in neutrophil recruitment necessary for extracellular pathogen clearance and the promotion of certain autoimmune conditions. We have previously demonstrated that natural Th17 (nTh17) cells develop within the thymus in a manner similar to that of natural T regulatory (nTreg) cells (Marks et al., Nat. Immunol. 2009), with activation in response to an increase of self-antigen due to tissue destruction and subsequent host protection via IL-22 secretion. In this study, we report microarray analysis of lymph node nTh17 cells, revealing specific patterns of gene expression compared to naïve, Th1, and nTreg cells. We identified 317 genes uniquely over- or under-expressed in nTh17 cells compared to controls. These results give new insights into the differences among naïve, nTreg, nTh17, and Th1 cells. We further identified two receptors -- IL-1R1 and IL-17RC -- that are expressed on nTh17 cells and play a role in their development and function. Development of nTh17 cells is hindered in the absence of IL1R1, and augmented in response to an increase of IL-1β. IL17-RC appears to be functional on nTh17 cells, in that it offers a way for the cells to regulate the levels of secreted IL-17A and IL-22.
The effect of B cell receptor affinity on lipid mediated B cell receptor antigen microclustering (109.1)
Authors: Yu-Yang Paul , Reddy A. , Raychaudhuri Subhadip 
Published: January 2023

Abstract
After encountering antigens (Ags), B-cell receptors(BCRs) with bound Ags assemble into microclusters then into a macrocluster. BCR recognition of antigen results in a monotonically increasing graded signaling response with increasing affinity for Ag, a robust feature that seems to be characterizing BCR-Ag affinity discrimination. Recent experiments indicate an important role of very early (within seconds) signaling events, such as formation of BCR-Ag microclusters, in this affinity discrimination process. Our current studies improve upon our most recent biophysical models for BCR-Ag microcluster and macrocluster formation by incorporating lipid-mediated BCR attraction factors. We examine the effect of (a) lipid and BCR concentration, and (b) varying attractive forces between different lipid and BCR pairings. Our studies indicate that a weak attraction between pairs of BCR molecules does not lead to microclusters. However, strong coupling between BCR and lipid (sphingolipids) molecules, that possibly arises upon antigen binding, generates microclusters of size similar to what has been observed in experiments. Our results indicate that microcluster size and number increase with increasing affinity while the formation times of such early BCR-Ag clusters decrease. These features can have important implications for the B cell affinity discrimination problem.
Dependence of TCR triggering on ligand three-dimensional freedom (109.19)
Authors: Ma Zhengyu , Janmey Paul , Finkel Terri 
Published: January 2023

Abstract
T lymphocytes (T cells) recognize antigens through the binding of T cell receptors (TCRs) to peptide ligands presented by MHC molecules (pMHCs) on antigen presenting cells (APCs). The mechanism of how pMHC-TCR binding triggers a signal from TCR is still unclear. One unique aspect of TCR triggering is that surface-anchored pMHC triggers TCR highly efficiently in a two dimensional setting, while soluble monomeric pMHC ligands with full three dimensional freedom have no activity. Here, we investigate the dependence of TCR triggering on the 3D freedom of pMHC ligands using highly flexible hetero-bifunctional poly(ethylene glycol) (PEG) polymer linkers. Fluorescence resonance energy transfer assay showed increased 3D freedom of ligands with increased linker length. As measured by IL2 production, T cells responded equally well to pMHCs anchored on surfaces with 0.56 nm, 3.1 nm and 12.7 nm linkers. T cell response started to decrease, however, when the linker was 22 nm long, and decreased further for the 32 nm linker. pMHCs anchored with the 48 nm linker still stimulated T cells IL2 production, although with only about one tenth the potency. Therefore, pMHC ligands with 3D freedom of up to 22 nm are well tolerated by TCR, but larger 3D freedom gradually reduces potency. Our findings argue against the kinetic segregation of TCR triggering but are in support of receptor deformation, a model of TCR triggering that tolerates increased ligand 3D freedom.
β-arrestin-1 negatively regulates inflammatory response to polymicrobial sepsis in mice (110.11)
Authors: Parameswaran Narayanan , Gonipeta Babu , Parvataneni Sitaram , Packiriswamy Nandakumar , Sharma Deepika 
Published: January 2023

Abstract
β-arrestins are scaffolding proteins that regulate a number of receptor signaling pathways including Toll-like receptors. We recently demonstrated that mice lacking either β-arrestin-1 or β-arrestin-2 are protected from lipopolysaccharide-induced lethality and have a markedly reduced inflammatory response. To assess the role of β-arrestin-1 in a clinically relevant model of sepsis, we subjected wild type and β-arrestin-1 knockout mice to cecal-ligation and puncture (CLP) to mimick septic peritonitis and polymicrobial sepsis. Surprisingly, we found that, mortality of β-arrestin-1 knockout mice was significantly enhanced compared to the wild type mice after CLP. Consistent with lethality, β-arrestin-1 knockout mice had markedly elevated inflammatory cytokine levels in the plasma, peritoneal cavity, and bronchoalveolar fluid. Enhanced systemic inflammatory response of β-arrestin-1 knockout mice was associated with significantly enhanced infiltration of immune cells into the peritoneal cavity after induction of septic peritonitis. Together, these results demonstrate that, contrary to its role in lipolysaccharide-TLR4 signaling in vivo, β-arrestin-1 is a negative regulator of inflammation induced by polymicrobial sepsis and that the phenotype of the mice may be related to a potentially aberrant immune response from excess infiltration of immune cells. These results also suggest that the role of β-arrestin-1 in this model is likely independent of its role in TLR4 signaling in vivo.
SerpinB1 inhibition of cathepsin G is critical for neutrophil survival and the maintenance of the bone marrow reserve of mature neutrophils in vivo (110.14)
Authors: Benarafa Charaf , Baumann Mathias 
Published: January 2023

Abstract
The bone marrow reserve of neutrophils is required for a rapid and effective mobilization to infected tissues. We recently reported that this reserve is considerably reduced in serpinB1-/- mice due to a survival defect of mature neutrophils. SerpinB1 inhibits the three neutrophil serine proteases (NSPs): elastase (NE), cathepsin G (CG) and proteinase-3 and is expressed at high levels in neutrophils but also in non-hematopoietic cells. Here, we found that, in bone marrow chimera, serpinB1 deficiency in hematopoietic cells was necessary and sufficient to reproduce the bone marrow neutropenia observed in serpinB1-/- mice. In addition, when irradiated mice were reconstituted with a 1:1 mixture of serpinB1-/- and wild type bone marrow cells, only a small percentage of the mature neutrophils were from the serpinB1-/- donor, whereas B cells of the two genotypes were found in equal proportions. Mice lacking serpinB1 as well as active NSPs due to deficiency in dipeptidyl peptidase I (serpinB1-/-.dppi-/-) had a normal neutrophil reserve indicating that one or more NSPs was involved in the bone marrow defect. Deficiency in CG alone, but not NE, was sufficient to fully restore a normal number of bone marrow neutrophils in serpinB1-/- mice. Collectively, these findings demonstrate that serpinB1 protects the neutrophil reserve in a cell autonomous manner and indicate a novel cell death pathway in neutrophils mediated by serine protease cathepsin G and regulated by serpinB1.
The TRPM2 ion channel is required for early innate immunity against Listeria infection (110.20)
Authors: Li Yuan , Knowth Heather , Heizer Justin , Mogan Jenny , Perraud Anne-Laure 
Published: January 2023

Abstract
TRPM2 is a non-selective cationic channel, which can mediate Ca2+ fluxes in response to H2O2, indicating a role in signaling as a sensor of oxidative stress. TRPM2 is functionally expressed in many immune cell types, and has been reported to be required for neutrophil chemotaxis and production of the chemokine CXCL2. In order to investigate the function of TRPM2 in response to a pathogen, we infected TRPM2-/- mice with Listeria monocytogenes (Lm). We found that TRPM2-/- mice show higher mortality and strongly elevated bacterial burdens already at an early stage of Lm infection. This susceptibility to Lm infection is not caused by defects in the recruitment of neutrophils, as neutrophil migration remains intact in Lm-infected TRPM2-/- mice. Because the production of IFNγ and IL-12 is reduced in TRPM2-/- mice, we conclude that TRPM2 can enhance the production of some cytokines. Bone marrow transfer experiments suggest that the susceptibility of TRPM2-/- mice to Lm infection might originate from both immune cells and nonhematopoietic cells. In sum, we have demonstrated the importance of TRPM2 in enhancing the crucial production of cytokines during early immunity against Lm.
Strong antibody responses to influenza vaccination are associated with cell survival/proliferation and pro-apoptotic immune traits (110.27)
Authors: Furman David , Kidd Brian , Shen-Orr Shai , Maecker Holden , Dekker Cornelia , Davis Mark 
Published: January 2023

Abstract
Vaccination is the most effective strategy to prevent and control infectious diseases through induction of antibodies that neutralize the pathogen. However, little is known on what immune traits underlie an effective antibody response. With the aim of finding correlates of vaccine response that predict the antibody titers against an influenza vaccine, we studied the antibody responses to the seasonal trivalent influenza vaccine in a young and older individuals, and assayed a comprehensive set of immune parameters that included whole blood gene expression, determination of serum cytokine levels, leukocyte subset frequencies and phosphorylation of signaling proteins upon stimulation of various peripheral blood cells. We have found that rise in antibody titers to influenza strains after vaccination is strongly associated with high pro-apoptotic and low cell survival/proliferation levels of diverse immune traits and genes that could be exploited to improve vaccine responses in those less protected.
Histone deacetylase inhibition facilitates GM-CSF-mediated expansion of myeloid-derived suppressor cells in vitro and in vivo (111.10)
Authors: Rosborough Brian , Castellaneta Antonino , Natarajan Sudha , Thomson Angus , Turnquist Heth 
Published: January 2023

Abstract
Recent studies have demonstrated anti-inflammatory and tolerance-promoting properties of chromatin-modifying histone deacetylase inhibitors (HDACi) through their ability to modulate dendritic cells and regulatory T cells. However, the influence of these agents on rare, immunoregulatory myeloid-derived suppressor cells (MDSC) has not been examined. C57BL/6 (B6) bone marrow (BM) cells were cultured with GM-CSF and the HDACi trichostatin A (TSA) for 5d. Cell lineage was identified by flow cytometry and putative MDSC purified by anti-Gr1 immunomagnetic bead selection. For in vivo experiments, mice received hydrodynamic infusion of GM-CSF or control enhanced green fluorescent protein plasmid then TSA for 5d. Splenic MDSC were isolated by Gr1 positive selection, and suppressive function was tested in allogeneic mixed leukocyte cultures. Exposure of GM-CSF-stimulated BM cells to TSA led to expansion of suppressive MDSC (CD11b+Gr1+) that correlated with increased numbers of hematopoietic stem and progenitor cells (HSPC; Lin-Sca-1+c-Kit+). TSA enhanced mobilization of splenic HSPC in vivo following GM-CSF administration and increased CD11b+Gr1+ cells in the BM and spleen. Increased numbers of Gr1+ cells that suppressed effector T cell proliferation were isolated from spleens of TSA-treated mice given GM-CSF. In conclusion, HDACi enhance GM-CSF-mediated expansion of MDSC in vitro and in vivo, suggesting a novel mechanism of the anti-inflammatory action of HDACi.
Characterization of Vibrio parahaemolyticus serotype O3:K6 activation of murine macrophage. (111.27)
Authors: Waters Stephanie , Parent Michelle , Blumerman Seth , Whitaker Brian , Joerger Torsten , Boyd Ethna 
Published: January 2023

Abstract
Vibrio parahaemolyticus is the leading cause of seafood-related bacterial gastroenteritis in the United States. There is a dearth of literature regarding the host response to, and subsequent elimination of, infection with this pathogen. Here, we have developed an in vitro model using the virulent clinical isolate V. parahaemolyticus RIMD2210633, an O3:K6 serotype. We determined that this isolate could infect RAW264.7 cells, a murine macrophage cell line and bone marrow derived macrophage (BMDM), resulting in the production of the early proinflammatory cytokines interleukin-1 alpha (IL-1α), interleukin 6 (IL-6) and interleukin 10 (IL-10). Additionally, infected RAW264.7 macrophage displayed increased surface CD86, CD40 and class II MHC expression while displaying a decrease in TLR4. Concurrently, we investigated the production of reactive oxygen species (ROS) by both RAW264.7 and BMDM infected with this virulent clinical strain. We report that in response to infection, both types of macrophage demonstrate increased production of ROS. We have determined that infection of macrophage by a virulent clinical isolate of Vibrio parahaemolyticus results in immune activation as demonstrated by increased cell surface molecules and proinflammatory cytokine production. Characterization of this response will provide the foundation to understand elimination of this organism from the infected host.