bluuebunny/crossref_metadata_2025_split huggingface dataset:
Distinct hypoxic molecular mechanisms differentially regulate human vs. mouse Interleukin 1β gene expression in monocytes/macrophages
Authors: Macar David A , Pulugulla Sree H , Adamik Juraj , Mitta Priyanka , Galson Deborah L , Auron Philip E 
Published: August 2023

Abstract
Interleukin 1β (IL-1β) is an important cytokine, whose regulation is distinct from that of Tumor Necrosis Factor (TNF). We previously reported that LPS/TLR4 initiates hypoxia in mice, with HIF-1α binding the murine Il1b gene, suggesting that TLR4 directly activates Trained Innate Immune Memory (TIIM). To address whether human monocyte IL1B gene regulation parallels that of mouse, mRNA and chromatin immunoprecipitation (ChIP) kinetics, with small molecule inhibitors under either normoxia or hypoxia, were evaluated. IL1B transcription kinetics in Lipopolysaccharide (LPS)-treated human THP-1 monocytes revealed an Immediate-Early (IE) phase of IL1B gene induction, requiring Spi1/PU.1, NF-κB and C/EBPβ transcription factors (TF), followed by a late-phase of lower-level continuous non-tolerized TIIM expression that depends upon hypoxia-inducible TFs. We observed that Spi1/PU.1 is required for IL1B gene transcription, performing a critical role in inducing the promoter for IE expression via a TAF1-independent mechanism. Late HIF-2α-dependent IL1B expression is due to LPS pseudo-hypoxic stabilization of the labile HIF factor. In contrast to IE activation, late-phase transcription revealed minimal dependence on NF-κB due to human-specific competition for an overlapping NF-κB/HIF enhancer element. Our studies reveal that IL1B in naïve THP-1 human monocytes binds HIF-2α, not HIF-1α, while PMA treatment morphologically polarizes THP-1 macrophages to bind both HIF isoforms at IL1B. Additionally, bioinformatic screening revealed other immunologically important genes regulated by similar mechanisms, providing insight for novel therapeutic targeting of transcription factors other than NF-κB.
Interleukin Foundation, Denver Colorado
Disrupting CXCR2-mediated MDSC trafficking enhances antitumor efficacy of vaccinia virotherapy
Authors: Tan Zhiwu , Chiu Mei Sum , Yue Ming , Song Youqiang , Man Kwan , Chen Zhiwei 
Published: August 2023

Abstract
Oncolytic virotherapy aims to potentiate antitumor responses via multiple mechanisms, including direct tumor lysis, increasing immune cell infiltration, modulating innate and adaptive immune interactions, and vascular modification. In an ideal situation, the oncolysis leads to release of tumor antigens and danger signals, to attract immune cells particularly dendritic cells (DC) into the tumor microenvironment (TME) and to recruit functional cytotoxic T lymphocytes (CTL). However, inflammation in the TME also has detrimental effects to promote cancer progression through reducing intratumoral T cell viability, promoting cancer cell proliferation and angiogenesis, and attracting immune suppressive cells. This complex balancing act dictates the outcome of oncolytic virotherapy and is yet fully understood. In this study, we demonstrated that in situ vaccinia virotherapy primarily recruited polymorphonuclear myeloid derived suppressor cells (PMN-MDSC) into the TME where they exhibited strong suppression of T cell effector function in a ROS-dependent way. Single-cell RNA sequencing analysis confirmed the heightened suppressive activity of PMN-MDSC at the transcriptomic level and identified CXCR2 as a therapeutic target expressed on PMN-MDSC. Abrogating PMN-MDSC trafficking by CXCR2-specific small molecule inhibitor during in situ vaccinia virotherapy exhibited enhanced antitumor efficacy in three syngeneic cancer models, through manipulating MDSC and T cell populations in the TME, activating CTL and skewing suppressive TME into an antitumor environment. Our results warrant clinical development of CXCR2 inhibitor in combination with oncolytic virotherapy.
Hong Kong Research Grant Council (TRS: T12-703/19-R and T11-709/21-N; CRF: C1134-20G and C7156-20G); Hong Kong Health and Medical Research Fund (HMRF 05162326), the Hong Kong Pneumoconiosis Compensation Fund Board (PCFB).
Inhibition of Ly-49/LILRB-MHC-I interactions by anti-MHC-I augments innate and adaptive immunity
Authors: Panda Abir Kumar , Natarajan Kannan , Sinha Surajit , Boyd Lisa F , Jiang Jiansheng , Teke Martha E , Hernandez Jonathan M , Margulies David H , Shevach Ethan M 
Published: August 2023

Abstract
Mouse NK cells recognize MHC-I antigens via stochastically expressed inhibitory Ly49 receptors. The loss of MHC-I expression on tumor cells (“missing self”) abrogates inhibitory signals, resulting in NK activation. We have identified an anti-mouse pan MHC-I mAb (M1/42), which blocks Ly49-MHC-I interactions but not TCR-MHC-I interactions. Administration of M1/42 in vivo markedly activated IFNg-producing NK cells that further drove the proliferation of NK cells and memory phenotype (MP) T cells and profoundly augmented adaptive immunity against viral infection and cancer metastasis. In contrast to mouse Ly-49 antigens, human killer cell inhibitory receptors bind to HLA at a site overlapping the TCR binding site and blocking of KIR binding to MHC-I would inhibit TCR recognition. However, two anti-pan-human MHC-I abs (DX17 and W6/32) markedly induced NK cell proliferation and IFNg production in cultures of human PBMC. DX17 potently blocked the interaction of leukocyte Ig-like inhibitory receptors LILRB1, B2, B3 and B5 with human MHC-I but had no effect on TCR-MHC-I interactions. The crystal structure of a DX17 Fab/MHC-I complex reveals that the footprint of DX17 overlaps the LILRB1 binding site on MHC-I. Administration of W6/32 Fab to humanized mice (PBMC reconstituted NSG or NK cell reconstituted NOG-IL-15) induced human NK and MP T cell proliferation. Marked reduction of tumor size was seen when NOG-hIL-15Tg mice were reconstituted with CD3−cells and then treated with W6/32 Fab. DX17 Fc silenced mAb (DX17 LALAPG) activated human tumor infiltrating lymphocytes and monocytes. These results strongly suggest that inhibition of LILRB-MHC-I interactions by anti-MHC-I in humans may result in marked augmentation of anti-tumor immunity.
This work was supported by the Intramural Research Program of NIAID, NIH.
Investigating molecular mimicry by microbial peptides in the induction of experimental autoimmune encephalomyelitis
Authors: Schwegman Lance , Bartsch Brenden , Abdul-Baki Nawal , de Oca Arena Maria Montes , Negron Austin , Forsthuber Thomas 
Published: August 2023

Abstract
Multiple sclerosis (MS) is an incurable neuroinflammatory autoimmune disease in which a patient’s immune system targets the myelin sheath of neurons. This impairs neuronal signaling to the periphery, manifesting as severe pain, loss of vision, and partial paralysis. Several environmental and genetic risk factors such as the DRB1*1501 haplotype have been identified, but the exact etiology of this disease remain unclear. It is thought that MS is primarily mediated by myelin-reactive CD4+ T cells, however, the autoantigen epitopes targeted are diverse and vary between patients. Furthermore, certain peptides from these autoantigens share amino acid sequence similarities with those of microbial peptides. This is the basis for a phenomenon known as “molecular mimicry”, in which these similarities are sufficient to activate autoreactive CD4+ T cells. Previous work in our lab using the mouse model of MS, experimental autoimmune encephalomyelitis (EAE), found that immunization of DRB1*1501 mice with a peptide from M. avium generates both M. avium- and myelin basic protein (MBP)-reactive CD4+ T cells, though the presence of these cells failed to induce disease. We have previously demonstrated that immunization with suboptimal amounts of multiple myelin-derived peptides, which would not induce EAE individually, result in EAE if combined. We therefore hypothesize that there is a threshold effect in which the concurrent presence of multiple microbial peptides with structural similarity to myelin can contribute to induction of EAE in transgenic DRB1*1501 mice. With the data from this study, we hope to clarify the role of microbial infection in the pathogenesis of MS.
This work was supported by grant RG1602 from the National Multiple Sclerosis Society (T.G.F.), support by the Jesse H. & Mary Jones Gibbs Endowed Chair (T.G.F.), support by grant G12MD007591 from the National Institute on Minority Health and Health Disparities, and NIH/NIBIB ESTEEMED grant R25EB027605 (LS), support by NIH grant R01NS117742 (T.G.F.).
DM functions differently in thymic antigen presentation cell subsets in development of autoreactive CD4+ T cells
Authors: Zhou Zemin , Wang Xiaomin , Cordero Bethanie , Evavold Brian D , Jensen Peter E 
Published: August 2023

Abstract
Autoreactive CD4+ T cells broadly exist in healthy individuals and potentially cause autoimmune diseases; however, why they can escape from thymic negative selection is still controversial. We observed that the activity of DM, a peptide epitope editor in MHC class II antigen presentation pathway, is differentially regulated in different thymic antigen presenting cells (APC). It is high in cTEC that involved in cortical positive selection, but low in mTEC, B cell, pDC and cDC that mediate negative selection in medulla, while it remains high in all types of peripheral APC. The molecular mechanism of differential regulation is still unknown. It is not directly inhibited by DO, a negative regulator of DM that directly competes DM catalytic site with peptide-MHC class II complex, since DM editing activity remains low in those thymic medulla APC in DO−/− mice. We further confirmed that presentation of autoantigen epitope MOG35–55 for thymic positive selection and in vitro activation of autoreactive CD4+ T cells in EAE, a mouse model of human multiple sclerosis disease, is DM dependent. This is also true for presentation of insulin epitope B9–23 to activate autoreactive CD4+ T cells restricted to type 1 diabetes associated HLA-DQ8. Our findings highlighted a fundamental mechanism that immune system differentially regulates DM activity in thymus to balance the efficiency of negative selection to minimize autoimmunity and the maximum of T cell repertoire to defend infection; however, the DM-dependency property of certain autoantigen epitopes accidently caused the failure deletion of autoreactive CD4+ T cells.
Investigating the requirement of IL-17A and IFNg in EAE disease development using HLA-DR3.IL-17A−/−.IFNg−/− transgenic mice
Authors: Turner Ti-Ara J , Peterson Stephanie , Shahi Shailesh , Mangalam Ashutosh K 
Published: August 2023

Abstract
Multiple sclerosis (MS), an autoimmune disease of the central nervous system, is thought to be mediated by autoreactive CD4+ T cells producing IL-17A and IFNg. However, it is unclear if these cytokines are essential for disease development, progression, or both. We have shown that neither IFNg nor IL-17A, alone, are required for the development of disease in experimental autoimmune encephalomyelitis (EAE), a mouse model of MS, but the absence of either results in different disease phenotypes. Specifically, HLA-DR3(DRB1*0301) (DR3).IFNg−/− mice develop severe atypical EAE characterized by increased levels of IL-17A, while DR3.IL-17A−/− mice develop mild, classical EAE. These data suggest that these cytokines may have compensatory roles. To further investigate the roles of these cytokines in EAE, we generated HLA-DR3.IFNg−/−.IL-17A−/− double knockout (DKO) mice and characterized their immune profiles, gut microbiomes, and disease phenotype. Our data show that DKO mice harbor distinct myeloid and CD4+ T cell profiles, myelin antigen-specific immune responses, and gut microbiota. Interestingly, DKO mice develop atypical EAE mimicking the disease phenotype of IFNg−/− mice. Thus, our data suggest that factors other than IL-17A and IFNg mediate atypical EAE susceptibility. Further characterizations of disease are ongoing in DKO mice to better define the precise roles of IL-17A and IFNg in the pathology of MS/EAE.
NIAID/NIH (1R01AI137075-01) and a generous gift from Margaret Heppelmann and Michael Wacek.
MHV-68 induces central nervous system autoimmunity in an MBP-specific TCR transgenic mouse model of multiple sclerosis
Authors: Deffenbaugh Joshua L , Lovett-Racke Amy E 
Published: August 2023

Abstract
Multiple Sclerosis (MS) is a demyelinating autoimmune disease of the central nervous system. Latent infection with Epstein-Barr virus (EBV) has been identified as a necessary yet insufficient factor in the development of the disease. Several groups have demonstrated that the murine EBV analogue, MHV-68, exacerbates disease severity in experimental autoimmune encephalomyelitis (EAE). However, the induction of EAE requires immunization and does not fully replicate the clinical features of MS. We sought to develop a virus-inducible model that accurately represents MS etiology and does not rely on classical EAE immunization. Using a transgenic mouse line with a myelin basic protein-specific T cell receptor, we found that MHV-68 induces demyelinating disease in 72% of infected mice. These mice exhibit clinical features such as optic neuritis, incontinence, and head tilt, which are commonly observed in MS patients but not in mice with EAE. This phenomenon was specific to MHV-68 and was not seen with other viral pathogens including PR8 influenza. Our work demonstrates that latent gammaherpesvirus infection can drive CNS autoimmunity in genetically predisposed mice without prior EAE induction, thus providing a more natural murine model of MS.
National Institute of Health R01AI140741-04
Exhausted CD8 T cell progenitors are sustained with TCR engagement during anti-tumor responses
Authors: Lan Xin , Mi Tian , Youngblood Ben A 
Published: August 2023

Abstract
T cell exhaustion is a major contributor to tumor immune invasion. The durability of an anti-tumor response is in part determined by the persistence of exhausted CD8 T cell progenitors (Tpex) that reconstitute the effector T cell pool. While it has been reported that Tpex are able to survive without antigen, the role of TCR engagement in regulating Tpex self-renewal during tumor progression remains to be fully explored. Here, we used a Lewis lung carcinoma model where a robust or dampened TCR signal was elicited resulting in bona fide tumor-infiltrating Tpex. Longitudinal analysis of tumor-specific CD8 T cells revealed that robust TCR stimulation was required for the formation and maintenance of the Tpex reservoir in tumor-draining lymph nodes (tdLNs). Replenishment of tumor-infiltrating Tpex was abrogated by suboptimal priming despite a generation of central memory-like T cells in tdLNs. Moreover, attenuated TCR engagement substantially accelerated the terminal differentiation of optimally primed Tpex. Chromatin accessibility and whole genome DNA methylation profiling revealed that Tpex-associated epigenetic programs were significantly enriched in optimally engaged T cells in tdLNs. Additionally, tumor-infiltrating sub-primed Tpex gained more Ets1 motifs while Tpex established from robust TCR stimulation acquired greater chromatin accessibility at Tcf-1 targeting loci. These Tcf-1 targets were further validated to be Tpex-specific when compared to those in naive T cells. Collectively, our results highlight the importance of TCR engagement in sustaining Tpex during tumor progression.
Early T cell infiltration correlates with anti-CTLA4 treatment response in the P815 mastocytoma model
Authors: Almonte Andrew Allan , Cavic George , Neeman Teresa , Fahrer Aude M 
Published: August 2023

Abstract
Immune checkpoint blockade (ICB) antibodies are a revolutionary class of cancer treatment, but only approximately 30% of patients receive a lasting benefit from therapy. Pre-clinical studies using animals from the same genetic backgrounds, challenged with the same cancer models, also show non-uniform responses. Most mouse studies that have evaluated tumour-infiltrating leukocytes (TILs) after ICB therapy cannot directly correlate their findings with treatment outcomes because terminal methods were used to acquire immune infiltrate data. In the present study, we used fine-needle aspiration (a non-terminal sampling method) to collect multiple aspirates over several days from subcutaneously implanted P815 mastocytomas treated with ICB antibodies. These aspirates were then analysed with flow cytometry to directly correlate nine TIL populations from both the innate and adaptive arms of immunity with treatment success. We found that the P815 model responds well to anti-CTLA4 but not anti-PD1. Mice that regressed following anti-CTLA4 therapy showed a significant increase in CD8+ T cells on days 3, 5, and 7 and CD4+ T cells on days 5 and 7, and a simultaneous decrease in macrophages and monocytes on days 3, 5, and 7 post-treatment. We also found that P815 tumours sometimes regressed in response to non-specific isotype control antibodies, likely due to their binding with Fc receptors on the cancer cells. Our study is the first to directly correlate early tumour infiltration of T cells with anti-CTLA4 treatment success, thus providing a mechanistic clue toward understanding why alloidentical mice challenged with identical tumours do not respond uniformly to ICB therapies.
This project was funded by the Australian Government Research Training Program, the Lea Chapuis Memorial Fund, The Lionel & Yvonne Spencer and William G Maxwell Trusts administered through Perpetual’s IMPACT Philanthropy, and the generosity of Tim and Margaret Bourke.
Extracellular vesicles derived from a specific strain of commensal bacteria promote anticancer immune responses and synergize with anticancer therapies
Authors: Kim You-Me , Bae Jihong 
Published: August 2023

Abstract
Commensal microbiota regulates cancer development and influences the efficacy of anticancer therapies. To develop a novel microbiota-based anticancer therapy, we screened human intestinal bacteria for their ability to induce IL-12 production in dendritic cells (DCs). A specific strain of Lactobacillus bacteria and their extracellular vesicles (EVs) induced a high level of IL-12 production without a concomitant induction of IL-10 secretion. In addition, DCs stimulated with the Lactobacillus EVs promoted differentiation of Th1 and Tc1 cells in vitro. In mice, oral or intravenous administration of the Lactobacillus EVs reduced tumor growth in both subcutaneous tumor cell implantation and spontaneous colon cancer models by enhancing the production of IFN-γ and cytotoxic effector molecules in tumor-infiltrating T cells. The EVs also enhanced anticancer efficacy of an anti-PD-1 antibody and oxaliplatin treatment. The tumor growth inhibition by the Lactobacillus EVs was abrogated when mice were treated with IL-12-blocking antibody, confirming that the anticancer effect of the EVs depends on their ability to induce IL-12 production. By biochemical and genetic analyses, we identified that bacterial DNA within the Lactobacillus EVs is the main factor inducing IL-12 production in DCs via stimulation of TLR9. Accordingly, DNA purified from EVs of the specific Lactobacillus strain, but not of a closely related other Lactobacillus strain, was able to stimulate IL-12 secretion. Moreover, the EVs did not show IL-12 induction and cancer suppressive function in TLR9-deficient mice. Our results suggest that a rational selection of commensal bacteria-derived EVs can be a strategy to develop a new cancer immunotherapy.
Supported by grants from the National Research Foundation of Korea (2017M3A9F3047085, 2020R1A2C2011307)
A novel population of CD103-expressing CD56+ regulatory ILCs suppresses intratumoural T cells and are associated with poor prognosis in patients with ovarian carcinoma
Authors: Chung Douglas , Vakharia Jehan , Warner Kathrin , Jacquelot Nicolas , Sayad Azin , Han SeongJun , Ghaedi Maryam , Garcia-Batres Carlos , Elford Alisha R , Matthews Jessica A , Wang Ben X , Nguyen Linh T , Shaw Patricia A , Clarke Blaise A , Bernardini Marcus Q , Ferguson Sarah E , Crome Sarah Q , Ohashi Pamela S 
Published: August 2023

Abstract
Regulatory innate lymphoid cells (ILCregs) are an emerging family of immunoregulatory cells that suppress innate and adaptive immunity in the context of diseases, including cancer. However, there is currently a lack of lineage-defining surface markers or transcription factors (TFs) that distinguishes ILCregs from other subsets of ILCs. Moreover, the functional role of ILCregs within the tumour microenvironment (TME) has not been well established. In this study, we uncovered a novel population of CD103-expressing CD56+ ILCregs within the TME that correlated with poor recurrent-free survival (RFS) in patients with epithelial ovarian carcinoma (EOC). CD103+ ILCregs expressed distinct surface markers and TFs that distinguishes them from canonical CD56+ natural killer (NK) cells. Moreover, intratumoural CD103+ ILCregs expressed markers (i.e., CD39, CD69, CD101, TIGIT) and transcriptomic profiles that are shared with Tregs, suggesting that they may have immunoregulatory properties. We found that ascites-derived TGF-β drives NK cell conversion into CD103+ ILCs that can suppress autologous CD4+ T cells in vitro. Furthermore, intratumoural CD103+ ILCregs suppressed autologous CD8+ T cells in vitro. Finally, we found that the abundance of CD103+ ILCregs in the TME were associated with reduced levels of both activated CD4+ T cells and CD8+ T cells. Overall, we have identified CD103+ ILCregs as distinct immunoregulatory cells that suppresses T cells within the TME of patients with EOC. Further untangling of the complex networks of immune regulation, including ILCregs, may give rise to novel therapeutic targets to enhance anti-tumour immunity and improve clinical response rates to immunotherapies.
This work was supported by a CIHR foundation award (CIHR FDN #143220), a TRANSCAN CIHR grant (CIHR – TRN #184713), a TRI grant from the Ontario Institute for Cancer Research (TRI OICR GCS #108796), and the Terry Fox Research Institute (TFRI-iTNT #1060). This project was also generously funded in memory of Mr. JIM JoTak under the Canadian Cancer Society (CCSRI #706152).