bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lack of p53 augments anti-tumor functions of cytolytic T cells (VAC11P.1005)
Authors: Banerjee Anirban , Thyagarajan Krishnamurthy , Kesarwani Pravin , Mehrotra Shikhar 
Published: January 2023

Abstract
Various effects of altered p53 expression are known with reference to uncontrolled cell proliferation, senescence and cell death. Loss of p53 also induces spontaneous inflammatory lesion and Treg deficiency. Only minor differences in proliferation, apoptosis, and maintenance of ‘non-self’ viral antigen specific T cells have been previously reported. However, the role of p53 in controlling T cell response to ‘self’ tumor epitope has not been comprehensively investigated. The h3T TCR transgenic mice with human tyrosinase epitope reactive T cells were thus developed on p53 deficient background and in vitro/in vivo analysis performed. Our data shows that TCR transgenic T cells from p53 KO mouse in comparison to wild type T cells exhibited increased proliferation, higher IFN-g secretion, enhanced cytolytic capacity, higher expression of stemness gene signature and were less susceptible to cell death upon restimulation with the cognate antigen. The effect of p53 inhibition on increased glycolytic effector functions was mirrored when treating human TCR transduced T cells with p53 inhibitor pifithrin-µ. Finally, the increase in effector function after p53 inhibition also correlated to the improved control of subcutaneously established murine melanoma after adoptive transfer of T cells. Thus, our data highlights the key role of p53 in metabolically regulating the tumor epitope specific T cell response and has potential translational significance in adoptive T cell therapy.
Comparative combination cancer immunotherapy with vaccination, checkpoint inhibition and TNFRSF stimulation (VAC12P.1021)
Authors: Schreiber Taylor , Podack Eckhard 
Published: January 2023

Abstract
Therapeutic tumor immunity requires the presence and activation of tumor antigen specific CD8+ T cells and migration of activated tumor-antigen specific CD8+ T cells into a tumor microenvironment where immunosuppressive barriers have been eliminated. Antibody mediated blockade of CTLA-4 and PD-1 is a clinically effective strategy to dampen tumor mediated immunosuppression in a minority of patients with advanced cancer, and this approach may be potentiated through vaccination to prime additional CTL clones and through direct stimulation of T cell costimulatory molecules of the TNF superfamily. Here we provide a systematic comparison of anti-tumor vaccination (3-MCA sarcoma and B16 melanoma) with either heat shock protein gp96-Ig or traditional peptide/adjuvant vaccines given alone or in combination with CTLA-4, LAG-3 or PD-1 blockade and direct T cell costimulation via OX40, 4-1BB and TNFRSF25. These studies demonstrate that both TNFRSF4 and TNFRSF25 independently and additively costimulate vaccine induced CD8+ T cell proliferation following both primary and secondary antigen challenge. When combined with checkpoint inhibition in therapeutic murine orthotopic tumor models, synergistic anti-tumor activity was observed. These studies highlight the complementary activity of vaccination, checkpoint inhibition and direct T cell costimulation, which may guide the application of combination immunotherapy for effective anti-tumor immunity.
Targeting multiple ErbB family members by EGFR peptide immunization. (VAC12P.1016)
Authors: Doyle Hester , Koski Raymond , Bonafé Nathalie , Bruck Ross , Tagliatela Stephanie , Gee Renelle , Mamula Mark 
Published: January 2023

Abstract
A major breakthrough in cancer treatment has been the development of monoclonal antibodies targeting tumor antigens. A majority of solid tumors overexpress the epidermal growth factor receptor (EGFR). Current treatments for EGFR overexpressing tumors include anti-EGFR monoclonal antibodies alone or in conjunction with standard chemotherapy or other EGFR inhibitors. While monoclonal antibody treatment is efficacious in some patients, drawbacks include the high cost of treatment, side effects associated with multiple drug infusions, and the development of antibody-resistant tumors. As an alternative to monoclonal antibody treatment, we have focused on peptide-based vaccination to trigger long lasting natural anti-tumor antibodies. Mice immunized with membrane-proximal epitopes in the extracellular domain of EGFR generate antibodies against EGFR as well homologous regions of the EGFR family members HER2 and HER3. HER2 and HER3 form heterodimers with EGFR and compensate for the lack of signaling through EGFR. EGFR peptide immune serum inhibits in vitro growth and promotes tumor killing of both human EGFR+ and HER2+ EGFR- tumor cells. A multi-specific tumor vaccine that targets multiple EGFR family members will provide greater tumor targeting than single agents alone while providing long-lasting immunity.
Bovine central memory T cells are highly proliferative in response to bovine tuberculosis infection. (VET2P.1033)
Authors: Fernanda Maggioli Mayara , Palmer Mitchell , Vordermeier H. Martin , Whelan Adam , Waters Wade Ray 
Published: January 2023

Abstract
Long-term (i.e., 14 days) cultured IFN-γ ELISPOT assays measure central memory T cell (Tcm) responses in both humans and cattle. With bovine tuberculosis, vaccine-elicited long-term IFN-γ ELISPOT responses correlate with protection. In other species, Tcm’s posses low activation threshold and are highly proliferative. It has been shown that Tcm’s accounts for 75% of long-term cultured cells. The objective of this study was to access the proliferative capability of Tcm cells compared to 6 day cultured cells (n = 6) in response to aerosol Mycobacterium bovis infection. Long-term cultured PBMCs from infected cattle were stimulated with M. bovis purified protein derivative (PPDb), rESAT-6:CFP10 (E:C), rTB10.4 and rAg85A for 13 days. Next, cells were stained with CellTrace dye and re-stimulated with E:C in the presence of fresh autologous adherent cells for an additional six days (20 days). In response to E:C, long-term cultured were mainly CD4+ cells and were more proliferative (~ 48%) than 6d cultured cells (27%; p=0.001). Long-term cultured cells were: ~30% Tcm (CCR7+, CD45RO+), ~48% Tem (CCR7-, CD45RO+), ~8% effector (CCR7-, CD45RO-) and &lt;1% of naïve cells (CCR7+, CD45RO-). Six day cultured cells were: ~16% Tcm (p=0.01), ~47% Tem, ~42% effector (p=0.001) and &lt; 1% naïve cells. These findings demonstrate that bovine Tcm cells present high proliferative capability as compared to short-term cultured cells.
Sequence and structural models of a bovine monoclonal antibody Fv region specific for bovine herpesvirus 1 glycoprotein D (VET2P.1037)
Authors: Levings Randall , Roth James 
Published: January 2023

Abstract
The cDNA of heterohybridoma mRNA encoding the variable domains of the light (VL) and heavy (VH) chains of an IgG1 bovine monoclonal antibody (MAb) neutralizing bovine herpesvirus 1 was commercially synthesized, cloned and sequenced. The variable (V) light chain sequence had highest identity with members of the V lambda family, 1a subfamily, and the joining (J) gene JL3, both commonly expressed in cattle. The V heavy chain sequence had highest identity with members of the VH1 gene family and JH1, also both commonly expressed in cattle. The VH nucleotide sequence had highest identity with the bovine diversity (D) gene DH3. The derived amino acid sequences were used to examine the complementarity-determining regions (CDRs) according to multiple systems. CDRL1-3 and CDRH1-2 were identified as belonging to or being similar to known canonical classes, and results from “H3 rules” were determined for CDRH3. Models of the Fv structure were derived using three on-line software packages. Overlapping sets of rodent and human MAb were used by the packages as templates for each framework and CDR structure individually. Predictions of the CDRL3 and CDRH3 configurations were more variable than that of other CDRs, and resulted in different paratope models. The results suggest sequences and crystal structures of MAb from a variety of species may be useful in describing additional canonical structures of immunoglobulins.
Impaired antibody effector function during persistent viral infection (VIR7P.1049)
Authors: Yamada Douglas , Elsaesser Heidi , Brooks David 
Published: January 2023

Abstract
Persistent viral infections are associated with dysfunctional B cell responses including polyclonal B cell activation, non-virus-specific hypergammaglobulinemia, and ultimately the inability to control infection. Using the lymphocytic choriomeningitis virus (LCMV) system of murine infection, we addressed whether similar to other antiviral mechanisms, the suppressive immune environment generated during persistent infection impacted antibody effector function. We demonstrate that high levels of circulating antibodies generated during persistent infection (termed hypergammaglobulinemia) impede antibody dependent phagocytosis and cell killing. As a result, otherwise highly efficacious cell killing antibodies are ineffective during persistent virus infection. Since antibodies are essential to the control of persistent infection, these observations have important implications immunologically for understanding the complex control of viral replication by antibodies as well as therapeutically for antibody immunotherapies aimed at viral clearance and secondary co-infections. Thus, we have identified a previously unrecognized mechanism of immune dysfunction during viral persistence with important implications for understanding the mechanisms of antibody function/dysfunction and affecting their ability to kill infected cells to control persistent virus infection.
Polyclonal CD4 TCR Affinities are not altered in chronic viral infection (VIR7P.1058)
Authors: Andargachew Rakieb , Martinez Ryan , Evavold Brian 
Published: January 2023

Abstract
The range of polyclonal CD4 T cell receptor (TCR) affinities that participate during the response to viral infection is currently unknown. Utilizing a highly sensitive two-dimensional micropipette adhesion frequency assay (2D), we determined the TCR affinity and frequency of CD4 T cells that expand and survive throughout multiple phases of the chronic and acute lymphocytic choriomeningitis virus (LCMV) T cell response. We discovered consistently more (4-5 fold) CD4 T cells specific for the IAb GP66-77 LCMV epitope than detected with pMHC II tetramer. The 2D identified lower affinity cells participate in the anti-viral response and are apparent at all time points of acute and chronic infection. Average TCR affinities measured at peak and later stages of the chronic response remained constant and equivalent to corresponding acute response measurements. However, programmed death 1 (PD-1) expressing CD4+ T cells late in chronic infection are functionally unresponsive despite static affinities. In contrast, memory cells in the acute response have a higher functional avidity compared to peak effectors (produce IFNγ in response to lower amount of peptide antigen) yet T cell memory is not restricted to select TCR affinities. Our findings suggest long term antigen exposure and functional enhancement/impairment exert no selective pressure in the survival or deletion of specific CD4 TCR affinities and TCR affinity alone does not always predict biological response.
Interaction of structurally diverse HSPs with ligand binding domains of CD91 (APP2P.110)
Authors: Mizote Yu , Pawaria Sudesh , Binder Robert 
Published: January 2023

Abstract
Select members of the Heat Shock Proteins (HSPs) are molecular chaperones, carrying diverse cargo including nucleotides, lipids, misfolded proteins and peptides. Immunization of mice or humans with HSPs leads to priming of T cell responses specific for the peptide antigens that they chaperone. HSPs, with the chaperoned peptides, in the extracellular environment have been shown to associate with the cell surface receptor CD91 expressed on antigen presenting cells (APCs). CD91 on APCs allow for endocytosis of HSP-peptide complexes and cross-presentation. Recently, we discovered that the same receptor CD91 acts as a signaling receptor for HSPs. HSPs were shown to cause the phosphorylation of the cytoplasmic tail of CD91, and thereby dictate the release of cytokines in a CD91-dependent manner. In this study, we aim to identify the domains on CD91 that are necessary for HSP binding. CD91 is expressed as a single polypeptide chain in the ER that is cleaved into the extracellular 515 kDa α-chain, included four ligand-binding domains, and the 85 kDa β-chain. By creating mini-gene constructs representing the ligand binding domains of CD91, the association of each HSP with each construct can be examined. The completion of this study will explain how the structurally diverse HSPs bind to a single receptor, necessary for priming immune responses.
T cell cross-reactivity to self peptide:MHCII shapes the foreign peptide: MHCII-specific CD4+ T cell repertoire (APP2P.112)
Authors: Nelson Ryan , Beisang Daniel , Jenkins Marc 
Published: January 2023

Abstract
The sizes of naïve CD4+ T cell populations specific for different foreign peptide:major histocompatibility complex II (p:MHCII) ligands vary by several orders of magnitude. This variability is biologically significant because large naïve populations generate more effector cells during an immune response than small ones. We hypothesized that the size of a given foreign p:MHCII-specific population is influenced by negative selection due to cross-reactivity between the foreign peptide and self peptides. We found that the frequency of naïve T cells specific for a given foreign p:MHCII ligand was inversely related to the number of self peptides predicted to bind MHCII and sharing 4 TCR contact amino acids with the foreign peptide. In addition, foreign p:MHCII-specific populations that were very small in normal mice were preferentially increased in mice with defective negative selection. Furthermore, gene-targeted mice lacking individual self peptides predicted to be involved in negative selection showed increased responsiveness to cross-reactive foreign peptides. These results suggest that immunodominant foreign peptides have this property because the corresponding naïve CD4+ T cell population has been subjected to minimal negative selection on cross-reactive self peptides.
A unique human-like CD8+ iNKT cells in a humanized mouse model (APP2P.113)
Authors: Wen Xiangshu , Kim Seil , Lawrenczyk Agnieszka , Xiong Ran , Rao Ping , Casorati Giulia , Dellabona Paolo , Yuan Weiming 
Published: January 2023

Abstract
The distinct differences in CD1d/NKT lipid presentation systems in humans and mice largely account for the minimal success of Natural Killer T (NKT) cell-based anti-tumor clinical trials in humans, contrasting their strong anti-tumor effects in conventional mouse models. We aim to humanize mice at the molecular level to better model human CD1d/NKT lipid presentation in vivo. Previously, we reported a novel human CD1d knock-in (hCD1d-KI) mouse, which contain a human-like abundance of iNKT cells yet possess potent anti-tumor immunity by the iNKT cells (Proc. Natl. Acad. Aci. USA 110: 2963-8, 2013). To further humanize the CD1d/NKT lipid presentation system, we have introduced the human Vα24 TCR transgene into the KI mice. These mice have comparable numbers of iNKT cells in thymus and spleen, but significant reduced numbers in liver comparing to Vα24Tg mice. These iNKT cells predominantly express mouse Vβ8 TCR, the homolog of human Vβ11, with reduced CD4 expression. Importantly, we detected in these mice a unique population of CD8+ iNKT cells, which exist in human, but not in wild type mice. Bone marrow transfer experiments suggested that CD8+ iNKT cells are hCD1d-dependent. These CD8+ iNKT cells produce cytokines upon activation and are cytotoxic to B16 melanoma cells in vitro. The hCD1d KI-Vα24Tg mice will allow more accurate in vivo modeling of the human CD1d lipid presentation to human iNKT cells and will facilitate the preclinical assessment of iNKT cell-based therapies.
Unusual antigen recognition provides clue to pathogenicity of diabetogenic CD8 T cell (APP2P.101)
Authors: Mukherjee Gayatri , Lamont Deanna , Prakash Rajesh , Samanta Dibyendu , Almo Steven , DiLorenzo Teresa 
Published: January 2023

Abstract
The defined length restriction as well as preference for amino acids at particular positions for each MHC allele is imposed by the physical as well as chemical nature of the peptide binding groove of the MHC molecule. Accordingly, the preferred peptide for the mouse MHC class I allele H-2Db is a 9mer with anchor residues N at P5 and M/I or L at position 9. However, in this study, we found that AI4, one of the most pathogenic CD8 T cell clones that participates in type 1 diabetes pathogenesis, recognizes an unusual 7mer peptide from the β cell specific protein insulin (InsA14-20) in the context of H-2Db. Further investigation showed that a majority of NOD mice had islet infiltrating T cells that recognized InsA14-20 or mimotopes derived from it, making the AI4-like T cells a very prevalent population. Crystallographic analysis revealed that InsA14-20 shares two solvent-exposed residues with all previously identified AI4 ligands which could explain the promiscuous nature of the AI4 T cell receptor. In addition, accessory anchoring residues were observed to compensate for the lack of the C-terminal anchor residue. In sum, the study demonstrates that less than ideal peptide-MHC interaction can still trigger T cell reactivity and contribute to disease pathogenesis, aided further by lack of thymic negative selection due to weak binding affinity.
Interaction of complement-coagulation factors in ischemia/reperfusion-induced injury in autoimmune prone (B6.MRL/lpr) mice (BA3P.205)
Authors: Moratz Chantal , Peng Suzette 
Published: January 2023

Abstract
Studies in the B6.MRL/lpr strain using the ischemia/reperfusion tissue injury (IR) model have demonstrated that complement activation is a key modulator of inflammatory tissue damage. The role of various components of the complement pathway (activation vs. deficiency) and the use of complement inhibition as therapeutic agents are areas of active research for systemic lupus erythematous (SLE). C1q inhibition is acutely effective in attenuating tissue injury in B6.MRL/lpr strain. Studies in our laboratory identified a C3-independent mechanism of complement C5a generation, terminal tissue injury, and systemic inflammation. The studies suggest a pathway which bypasses C3 by interacting with the coagulation cascade. Using the mesenteric IR model, we compared the extent of intestinal injury after IR when C1q inhibitors or coagulation inhibitors were administered. In our model C1q inhibition resulted in decreased tissue damage, thrombin generation, and C5a generation. Tissue Factor pathway inhibitor (TFPI) and anti-thrombin III attenuated tissue injury, thrombin generation, and C5a production but not C3b production. Interaction between thrombin and the complement pathway in the autoimmune mouse has significant clinical implications - especially in autoimmune diseases in which inflammation and hypercoagulability are known manifestations.
Involvement of necroptosis in the development of imiquimod-induced psoriasis-like dermatitis (BA3P.135)
Authors: Honda Tetsuya , Kabashima Kenji 
Published: January 2023

Abstract
Necroptosis is a form of programed cell death, in which receptor-interacting protein (RIP)1 and subsequent RIP3 kinase activation is a central pathway for its development. Necroptotic cells induce inflammation through the release of various cytokines or necrotic danger-associated molecular patterns. Recent reports indicated that mice with keratinocyte-specific necroptotic cell death exhibit severe chronic skin inflammation, which suggests the involvement of necroptosis in the pathogenesis of chronic skin inflammatory diseases, such as psoriasis. In this study, we investigated the involvement of necroptosis in the pathogenesis of psoriasis using an imiquimod (IMQ)-induced mouse psoriasis model. Daily application of IMQ to skin caused skin inflammation with psoriariform scaly erythema with epidermal and dermal thickening. In the skin, we detected positive signals of TUNEL both in the epidermis and dermis, suggesting the induction of programmed cell death in skin by IMQ application. In addition, RIP3 expression was significantly upregulated both in mRNA and protein level in the skin lesions. Administration of necrostatin-1, a specific inhibitor of RIP1 kinase, significantly reduced the severity of IMQ-induced psoriasis-like dermatitis. Immunohistochemical analysis revealed positive signals for RIP3 in the human psoriasis skin lesion. These results indicate the involvement of necroptosis in mouse psoriasis model, and suggest it's involvement in the pathogenesis of psoriasis.
Novel, critical roles of autophagy in dendritic cells and neutrophils to mediate experimental autoimmune encephalomyelitis (EAE) in mice (BA3P.201)
Authors: Bhattacharya Abhisek , Eissa N Tony 
Published: January 2023

Abstract
Multiple sclerosis (MS), an autoimmune disease of the central nervous system, affects more than a million people worldwide. Insufficient understanding of pathogenesis has precluded curative therapy for MS. Autophagy, a conserved bulk degradation process, is important in several immune functions, such as antigen presentation and infection control, but the potential roles of autophagy in regulating autoimmune diseases including MS are not well understood. To test our hypothesis that autophagy in innate immune cells is required to mediate MS, we generated conditional autophagy deficient mice where Atg7 or Atg5, essential autophagy genes, were deleted from dendritic cells (DC) or myeloid cells, induced experimental autoimmune encephalomyelitis (EAE), a mouse model of MS, and monitored disease severity. We found that autophagy deficiency in neutrophils ameliorated EAE by reducing neutrophil degranulation, resulting in failure of breakdown of blood-central nervous system barrier, a process required for EAE progression. Moreover, autophagy deficiency in neutrophils resulted in global reduction in neutrophil mediated-inflammation. Autophagy deficiency in DC, on the other hand, reduced both incidence and severity of EAE, secondary to decreased antigen presentation to T cells in the periphery. Our data show that autophagy is required for neutrophil-mediated inflammation. Our data further suggest that autophagy is a potential target for treating autoimmune diseases such as MS.