bluuebunny/crossref_metadata_2025_split huggingface dataset:
A subset of protective γ9δ2 T cells is activated by novel mycobacterial antigens (MPF5P.740)
Authors: Xia Mei , Hesser Danny , Sakala Isaac , Spencer Charles , Abate Getahun , Chatterjee Delphi , Dobos Karen , Hoft Daniel 
Published: January 2023

Abstract
γ9δ2 T cells provide a natural bridge between innate and adaptive immunity and are prominently induced by both tuberculosis (TB) infection and bacillus Calmette Guérin (BCG) vaccination. Mycobacteria-expanded γ9δ2 T cells represent only a subset of the simple phosphoantigen (IPP and HMBPP)-responsive γ9δ2 T cells, this subset expresses a more oligoclonal set of TCR sequences, and only this subset efficiently recognizes and inhibits intracellular BCG/Mtb. We have been searching for new mycobacterial antigens capable of inducing the unique subset of γ9δ2 T cells that can recognize mycobacteria-infected macrophages and mediate protective effects inhibiting intracellular mycobacterial growth. We first ruled out protein, nucleic acid and apolar lipids with basic separations and enzymatic digestions. Acid hydrolysis, which digests complex carbohydrate structures, had the largest effect on eliminating Mtb fraction specific activity. Organic extractions resulted in sub-fractions with &gt;100 fold enriched specific activity. A combination of MS, NMR, TLC indicate that methyl-glucose lipopolysaccharides (mGLP) are predominant components of the most active fractions. We are currently attempting to use synthetic techniques to confirm the specific activity of mGLP for induction of protective γ9δ2 T cells. These results have important implications for the development of new immunotherapeutic approaches for prevention/treatment of TB.
Inhibition of Interleukin 10 receptor signaling induces microbiota-dependent chronic colitis in Apolipoprotein E deficient mice (MUC5P.754)
Authors: Yeoh Beng San , Kumar Manish , Singh Vishal , Kennett Mary , Vijay-Kumar Matam 
Published: January 2023

Abstract
Apolipoprotein E (ApoE), a secreted protein, plays major role in cholesterol metabolism. ApoE is also known to exhibit anti-inflammatory properties. However, its role in the intestine, specifically during inflammation is not very clear. First, we verified upregulation of colonic ApoE transcripts in various models of murine acute and chronic colitis models. Age and gender matched ApoEKO mice and their WT littermates (n=5) were given either one or 4 weekly injections of IL-10 receptor (IL-10R) neutralizing mAb intraperitoneally and colitis development was monitored. ApoEKO mice given single injection of IL-10R mAb displayed acute colitis. Four weekly injections IL-10R mAb resulted in the development of chronic colitis as measured by colomegaly, splenomegaly and elevated colonic pro-inflammatory gene expression (TNFα, IFNγ) and histological score when compared to WT littermates. IL-10R neutralization also induced substantial levels of lipocalin 2, a general inflammatory marker in the feces, colon, and circulation in ApoEKO mice. Ablation of gut microbiota by broad-spectrum antibiotics substantially protected ApoEKO mice against IL-10R neutralization induced chronic colitis. In addition, cohousing ApoEKO mice with IL-10KO mice exaggerated spontaneous colitis (rectal prolapse) in IL-10KO mice when compared to WT suggesting ApoEKO harbor colitogenic microbiota. Collectively, our results demonstrate that ApoE plays a critical role in protecting the gut against inflammation.
Autoantigen-targeted therapy reinforces impaired central tolerance in autoimmune mice (THER5P.916)
Authors: Bonami Rachel , Rachakonda Amita , Hulbert Chrys , Thomas James 
Published: January 2023

Abstract
Immune tolerance breakdown precedes autoimmune disease. Receptor editing is an immune tolerance mechanism that alters BCR specificity to combat frequent autoreactivity in the developing B cell repertoire. Much of what is known about receptor editing derives from multivalent antigens, or soluble antigens which interact with the BCR with supra-physiologic affinity (1010 M-1). A system was therefore developed in which the BCR interacts with insulin autoantigen with a more physiologic affinity (107 M-1) to better reflect B cells that arise in the developing bone marrow repertoire. Surprisingly, circulating insulin was found to elicit receptor editing in non-autoimmune mice. This process occurred less efficiently in the type 1 diabetes-prone NOD strain, consistent with enhanced anti-insulin B cell escape into the periphery from the bone marrow observed in this strain. Receptor editing efficiency was enhanced by treatment with an insulin-targeting mAb that selectively eliminates anti-insulin B lymphocytes and prevents type 1 diabetes. A F(ab’)2 of this antibody also depleted developing anti-insulin B lymphocytes, confirming receptor editing as a central tolerance mechanism targeted by this approach. These studies show that a small protein hormone of modest affinity elicits receptor editing, but with less efficiency in the context of autoimmunity. This defect can be overcome with autoantigen-targeted therapy, which offers promise for the treatment of autoimmune disease.
Molecular mechanism underlying immune modulation during stem cell therapy of overt type 1 diabetes (THER5P.917)
Authors: Chen Weirong , Ukah Tobechukwu , Miller Mindy , Ellis Jason , Barik Subhasis , Zaghouani Habib 
Published: January 2023

Abstract
Type 1 diabetes (T1D) is an autoimmune disorder in which insulin-producing pancreatic beta-cells are selectively destroyed by self-reactive T cells. In previous studies, we incorporated glutamic acid decarboxylase 206-220 peptide into an Ig molecule and the resulting Ig-GAD2 chimera was shown to target diabetogenic T cells and prevent disease progression. However, despite its efficacy, Ig-GAD2 was not able to reverse overt T1D. In contrast, transfer of bone marrow (BM) cells alongside Ig-GAD2 induces recovery from overt T1D. This was due to effective immune modulation that stems from diminished function of the mammalian target of rapamycin (mTOR) complex 1. In addition, there was generation of BM-derived endothelial cells that contributed to the repair of islet vascular network which facilitated endogenous β-cell formation and restoration of β-cell mass. These findings suggest that targeting the function of mTOR synergizes with stem cell transfer to control overt T1D.
Inhibition of hyaluronan synthesis restores immune tolerance during autoimmune insulitis (THER5P.919)
Authors: Bollyky Paul , Kaber Gernot , Johnson Pamela , Gebe John , Preisinger Anton , Falk Ben , Gooden Michel , Vernon Robert , Bogdani Marika , Kuipers Hedwich , Campbell Daniel , Wight Thomas , Nagy Nadine 
Published: January 2023

Abstract
We recently reported that abundant deposits of the extracellular matrix polysaccharide hyaluronan (HA) characterize autoimmune insulitis in human type 1 diabetes (T1D) but the significance of these deposits was unclear. Here, we demonstrate that HA is critical for the pathogenesis of autoimmune diabetes. Using the DO11.10xRIPmOVA (DORmO) mouse model of T1D, we show that HA deposits are temporally and anatomically associated with the development of insulitis. Moreover, treatment with an inhibitor of HA synthesis, 4‑methylumbelliferone (4-MU), halted progression to diabetes even after the onset of insulitis. 4-MU reduced HA accumulation, constrained effector T-cells to non-destructive insulitis, and increased numbers of intra-islet Foxp3+ regulatory T-cells (Treg). Consistent with this, Treg differentiation was inhibited by HA and anti-CD44 antibodies and rescued by 4-MU in an ERK1/2-dependent manner. These data may explain how peripheral immune tolerance is impaired in tissues under autoimmune attack, including islets in T1D. We propose that 4-MU, already an approved drug used to treat biliary spasm, could be repurposed to prevent, and possibly treat, T1D in at-risk individuals.
Selective ROCK2 inhibitor reverses experimental chronic graft-versus-host disease via concurrent regulation of STAT3/STAT5 phosphorylation (TRAN1P.933)
Authors: Zanin-Zhorov Alexandra , Flynn Ryan , Luznik Leo , Nyuydzefe melanie , Panoskaltsis-Mortari Angela , Du Jing , Goodman Katelyn , Weiss Jonathan , Chen Wei , Serody Jonathan , MacDonald Kelli , Hill Geoffrey , O'Shea John , Waksal Samuel , Blazar Bruce 
Published: January 2023

Abstract
Rho-associated kinase 2 (ROCK2) was recently shown to be implicated in regulation of IL-21 and IL-17 secretion in mice and humans. Here, we report that the potent and highly selective ROCK2 inhibitor KD025 effectively reverses an established chronic graft-versus-host (cGVHD) murine model driven by IL-21 and characterized by an aggressive multiorgan system fibrotic disease. KD025 treatment leads to a dose dependent decrease in the development of pathogenic pulmonary function which correlates with a marked reduction of antibody and collagen deposition in the lungs of treated mice to levels comparable to non-cGVHD controls. The spleens of mice treated with KD025 had a decrease in the frequency of germinal centers associated with a reduction in STAT3 and concurrent increase in STAT5 phosphorylation, supporting the molecular mechanism of targeted ROCK2 inhibition in humans. The critical role of STAT3 activation in this cGVHD model was further confirmed by data showing that mice transplanted with inducible STAT3 deficient T cells or BM cells had pulmonary function comparable to the healthy negative controls. Finally, KD025 effectively blocked the progression of sclerodermatous cGVHD model characterized by improvements in weight loss, posture and skin integrity of treated animals. Together, these data demonstrate the importance of ROCK2 signaling in STAT3-dependent regulation of cytokine secretion and highlight the potential of targeted ROCK2 inhibition for cGVHD therapy.
Immunization with donor splenocytes in testis of recipient mice promotes induction of long-term survival of islet allografts transplanted in a conventional site (TRAN1P.920)
Authors: Dai Zhenhua , Xie Qingfeng , Zhang Shuzi 
Published: January 2023

Abstract
Immune responses are subdued in immune privileged sites, which provide a unique opportunity to prolong cellular allograft survival. We and others have previously shown that inducing tolerance of islet allografts transplanted in murine testes is easier than in conventional sites. However, it is not practical to transplant islets in human testes. Here we found that immunization of B6 recipients with irradiated Balb/C splenocytes through testicular injection, 7 and 14 days before islet transplantation under the kidney capsule, promotes long-term allograft survival induced by low doses of anti-CD40L (MR1) or CTLA4-Ig (0.1mg/day, days 0,2,4,6), with 75% islet allografts achieving long-term survival (&gt;120 days). Same Ab treatment without the immunization failed to do so. Immunization without MR1 or CTLA4-Ig did not prolong allograft survival. We also found that islet transplantation under renal capsule of previously immunized recipients generates much less CD44+CD8+ memory T cells but induces more CD4+CD25+ Tregs than under renal capsule of unimmunized recipients. These Tregs exhibited donor-specific suppression of alloimmune responses in vitro. These findings reveal new mechanisms of immune privilege and may provide novel approaches to inducing long-term allograft survival or transplant tolerance in both immunologically privileged and unprivileged sites.
Molecular identification of endothelial cell surface antigens using proteomic approach to the molecules recognized by antibodies in transplant recipients (TRAN1P.939)
Authors: Zou Yizhou , Hu Juan , Luo Weiguang , Li Tingting 
Published: January 2023

Abstract
It is known that transplant recipients may have antibodies to endothelial cells (EC) but not to lymphocytes, by which the rapid and irreversible destruction of allograft is induced. We characterize EC surface antigens using well-identified recipient sera with strong antibodies against EC. 9 serum samples from 7 patients with kidney allograft rejection and antibodies against freshly isolated human umbilical vein endothelial cells (HUVECs) were selected. Target antigen proteins of EC were immunoprecipited by serum antibodies and separated by SDS/PAGE, followed by protein identification with mass spectrometry. Monoclonal antibodies against HLA and MICA were used as the procedure control in our experiment. We successfully captured the HLA and MICA molecules from ECs by these mAbs respectively. Using patient sera, three proteins were identified in these experiments: 1) human MICA glycoproteins, already known surface molecules expressed on ECs and associated with antibody-mediated rejection; 2) human keratin 1, a protein known to be expressed on the surface of endothelial cells; 3) 70KDA (local name) molecule, a protein underwent investigation. A variety of antigens appears to be harbored on the surface of endothelial cells and can elicit immune responses in transplant recipients. Our results indicated that MICA, keratin 1 and 70KDA proteins might be important antigens in organ transplant rejection. The role of these molecules on transplant rejection requires further investigation.
IL-33/ST2 activation of IL-9-secreting T cells alters the balance of fatal immunity and tumor immunity (TRAN1P.926)
Authors: Ramadan Abdulraouf , Zhang Jilu , Griesenauer Brad , Kapur Reuben , Hanenberg Helmut , Sun Jie , Kaplan Mark , Paczesny Sophie 
Published: January 2023

Abstract
Allogeneic hematopoietic cell transplantation (HCT) is the most potent curative therapy for cancers of the bone marrow; however, graft-versus-host disease (GVHD) continues to be the major limitation to successful HCT, with mortality rates around 50%. Current strategies to suppress GVHD also compromise the beneficial graft-versus-tumor (GVT) activity. We have shown that elevated IL-33-sequestering soluble ST2 in the plasma is a risk factor for severe GVHD. In addition, the IL-9-secreting Th9 and Tc9 cell subsets have higher antitumor activity than Th1 and Tc1. We hypothesized that induction of the ST2/IL-33 pathway will both alleviate GVHD and increase GVT activity. Differentiation of Th9 with IL-33 increased expression of membrane ST2 (ST2L) and PU.1, a transcription factor that promotes IL-9 production. Adoptive transfer of IL-33-treated Th9 cells with bone marrow cells in HCT murine models showed less severe GVHD compared to Th9 without IL-33, or Th2 cells that are protective of GVHD. Polarization of total T cells with IL-33 to IL-9 secreting cells showed that IL-9 was also increased in Tc9 cells via Th9 help. Transcriptome analysis of IL-33-T9 cells showed increased expression of genes with anti-tumor activity. Higher GVT activity with IL-33-T9 cells was demonstrated in models of GFP+MLL-AF9 acute myeloid leukemia. Human IL-33-T9 cells also showed a strong anti-leukemia cytolytic activity. Thus, IL-33-T9 cells represent a promising curative cellular therapy following HCT.
Semaphorin7A Inhibition interrupts hypoxia induction of angiogenic factors in murine monocytes (TUM6P.963)
Authors: Garcia-Areas Ramon , Libreros Stephania , Keating Patricia , Karram Joseph , Castro Camilla , Iragavarapu-Charyulu Vijaya 
Published: January 2023

Abstract
We discovered that mammary tumor cells express high levels of the protein Semaphorin7A (SEMA7A) and that tumor-derived SEMA7A induces monocytes to secrete pro-angiogenic chemokines to enhance tumor growth. Decreased SEMA7A limits tumor growth and production of angiogenic CXCL-2/MIP-2 and VEGF-A by monocytes. The mechanisms controlling SEMA7A expression during tumor progression are largely unknown. Recent reports describe a hypoxia responsive element in the promoter of SEMA7A. It is well established that hypoxia enhances tumor growth by promoting angiogenesis and alternatively activating monocytes. We hypothesize that SEMA7A may be a hypoxia-inducible factor and its inhibition may deter production of monocyte-derived angiogenic proteins. Monocytes from wild-type (WT) and SEMA7A null BALB/c mice were exposed to CoCl2-induced hypoxia. CoCl2 induced expression of SEMA7A in both mammary cells and WT monocytes. Following hypoxic stimuli, WT monocytes increased production of CXCL2/MIP-2, VEGF-A and Chitinase-3-like protein1 (CHI3L1). However, SEMA7A null monocytes failed to respond to hypoxia, which may be attributed to an impaired MAPK signaling response. Thus, inhibiting SEMA7A may abrogate the detrimental effects of tumor induced hypoxia on monocytes. We are further delineating how the lack of host SEMA7A can impact mammary tumor growth in vivo. Understanding the role of SEMA7A may unravel important tumor-host immune interactions in breast cancer.
Defined combinations of cytokines plus survival factors drive the differentiation of human monocytic myeloid derived suppressor cells into M1- or M2-like macrophages (TUM6P.969)
Authors: Bayik Defne , Wang Jing , Gursel Ihsan , Klinman Dennis 
Published: January 2023

Abstract
Myeloid derived suppressor cells (MDSCs) support tumor progression by inhibiting the activity of tumor-infiltrating natural killer cells and T cells. The subpopulation represented by monocytic MDSCs (mMDSCs) is the most immunosuppressive on a per cell basis. We studied mMDSCs FACS purified from the peripheral blood of 20 healthy donors. Results showed that specific TLR agonists (targeting TLRs 4, 7, 8 and 9) induced these cells to differentiate into either M1- or M2-like macrophages. We then defined the soluble factors responsible for this maturation. Differentiation was optimized by the inclusion of maturation factors such as GM-CSF or PGE2 during culture. GM-CSF alone induced the maturation of only a minority of mMDSCs, but nearly all of these became M2-like, suggesting that that M2 generation represents the default differentiation pathway of mMDSCs. Additional study showed that optimal mMDSC differentiation required the addition of IL-6 (and that blocking IL-6 activity prevented differentiation). The type of macrophage generated was influenced by other environmental cytokines, including IL-12, IL-4, TNFa, IL-10 and IL-13. Thus, specific combinations of cytokines plus survival factors can be harnessed to generate M1- or M2-like macrophages, raising the possibility of selectively producing such cells for the treatment of malignancies or autoimmune diseases, respectively.
Tumor-associated macrophages and heparanase in lung cancer microenvironment. (TUM6P.970)
Authors: Castelo-Branco Morgana , Souza Heitor , Paschoal Marcos , Pavão Mauro , Rumjanek Vivian 
Published: January 2023

Abstract
Tumor-associated macrophages promote aspects of tumor initiation, growth, and progression. Tumor growth takes place in a complex microenvironment of stromal cells and extracellular matrix. Heparanase is the only known mammalian glycosidase capable of cleaving heparan sulfate. Its expression has been associated with tumor development. Immunohistochemistry and immunofluorescence were performed in samples of 37 lung cancer patients to assess heparanase, macrophages and lymphocytes presence and localization. All types of tumors expressed heparanase within the cytoplasm and nucleus. Adenocarcinoma showed the highest intensity and widespread distribution. The other types had similar intensity with a less widespread distribution. Tumor surroundings also presented heparanase co-expression with fibroblast, macrophages and epithelial cells. Heparanase expression correlates to TNM staging. The heparanase possesses a different distribution according to the type of lung tumor. Heparanase from fibroblasts might regulate the tumor microenvironment through HS cleavage, by enabling invasion and release of growth factors from extracellular matrix. We showed lung cancer TAMs expressing heparanase and described heparanase localization in the tumor microenvironment providing knowledge concerning lung cancer. Therefore, we suggest that heparanase can constitute a possible therapeutic target for lung carcinoma and that macrophages are attractive targets as part of combination therapy in cancer.
Lgr4 deficiency attenuates tumor formation by reprograming macrophage polarization in lung cancer (TUM6P.973)
Authors: Du Bing , Tan Binhe , Wei Yinglei , Qin Juliang , Qian Min , Liu Mingyao 
Published: January 2023

Abstract
Macrophage polarization is increasingly recognized as an important pathogenetic factor in tumor formation. Our previous study has shown that Lgr4 negatively regulates TLR2/4 associated pattern recognition in innate immune responses. However, the exact roles and mechanisms of Lgr4 in macrophage polarization remain largely unknown. Here, we found that patients with Lgr4-high lung cancers displayed much poorer survival than the rest of the cohorts. Meanwhile, Lgr4 is also aberrantly expressed at high levels in macrophages from clinical lung adenocarcinomas (ADs), implying the potential role of Lgr4 in tumor-associated macrophages (TAMs). In addition, the expression of Lgr4 in bone marrow derived macrophages (BMMs) was reduced by IFN-γ and increased by IL-4 significantly. Interestingly, Lgr4 deficiency BMMs showed a obviously increased M1 phenotypes and reduced M2 phenotypes. Accordingly, host deficiency in Lgr4 resulted in defective and reduced growth of subcutaneously implanted Lewis lung carcinoma (LLC). Consistent with the defective growth, LLC cells implanted into Lgr4 conditional knockout mice also displayed reduced TAMs and increased M1 like macrophages in tumor tissues, suggesting impaired TAMs polarization. These findings suggest that deletion of Lgr4 may inhibits tumor growth via reprograming TAMs polarization. Thus, Lgr4 expressed in TAMs may potentially become a novel target for cancer therapy.
IRF8 expressed in T cells regulates GM-CSF expression to control myeloid derived suppressor cell differentiation (TUM6P.955)
Authors: Paschall Amy , Zhang Rui-hua , Qi Chen-Feng , Bardhan Kankana , Peng Liang , Lu Geming , Yang Jianjun , Merad Miriam , McGaha Tracy , Zhou Gang , Mellor Andrew , Abrams Scott , Morse Herbert , Ozato Keiko , Xiong Huabao , Liu Kebin 
Published: January 2023

Abstract
During hematopoiesis, hematopoietic stem cells differentiate into granulocytes and macrophages via a distinct differentiation program that is controlled by myeloid lineage-specific transcription factors. Mice with a null mutation of IFN Regulatory Factor 8 (IRF8) accumulate CD11b+Gr1+ myeloid cells that phenotypically and functionally resemble tumor-induced myeloid-derived suppressor cells (MDSCs), indicating an essential role of IRF8 in myeloid cell lineage differentiation. However, whether IRF8 functions intrinsically or extrinsically in regulation of myeloid cell differentiation is not fully understood. Here we report an intriguing finding that mice with IRF8 deficiency only in myeloid cells exhibit no abnormal myeloid cell lineage differentiation. Instead, mice with IRF8 deficiency only in T cells exhibited MDSC accumulation. We further demonstrated that IRF8-deficient T cells exhibit elevated GM-CSF expression and secretion. Treatment of mice with GM-CSF increased MDSC accumulation, and adoptive transfer of IRF8- deficient T cells, but not GM-CSF-deficient T cells, increased MDSC accumulation in the recipient mice. Overexpression of IRF8 decreased GM-CSF in T cells. Our data determine that in addition to its intrinsic role as an apoptosis regulator in myeloid cells, IRF8 also acts extrinsically to repress GM-CSF expression in T cells to control myeloid cell lineage differentiation, revealing a novel mechanism of adaptive immune cell regulation of myelopoiesis in vivo.