Immunology
Abstract
Methotrexate (MTX) is a standard, first-line therapy for rheumatoid arthritis (RA); however, its precise mechanisms of action other than antifolate activity are largely unknown. We performed DNA microarray analyses of CD4+ T cells in patients with RA before and after MTX treatment and found that TP63 was the most significantly downregulated gene after MTX treatment. TAp63, an isoform of TP63, was highly expressed in human IL-17–producing Th (Th17) cells and was suppressed by MTX in vitro. Murine TAp63 was expressed at high levels in Th cells and at lower levels in thymus-derived Treg cells. Importantly, TAp63 knockdown in murine Th17 cells ameliorated the adoptive transfer arthritis model. RNA-Seq analyses of human Th17 cells overexpressing TAp63 and those with TAp63 knockdown identified FOXP3 as a possible TAp63 target gene. TAp63 knockdown in CD4+ T cells cultured under Th17 conditions with low-dose IL-6 increased Foxp3 expression, suggesting that TAp63 balances Th17 cells and Treg cells. Mechanistically, TAp63 knockdown in murine induced Treg (iTreg) cells promoted hypomethylation of conserved noncoding sequence 2 (CNS2) of the Foxp3 gene and enhanced the suppressive function of iTreg cells. Reporter analyses revealed that TAp63 suppressed the activation of the Foxp3 CNS2 enhancer. Collectively, TAp63 suppresses Foxp3 expression and exacerbates autoimmune arthritis.
Authors
Kensuke Suga, Akira Suto, Shigeru Tanaka, Yutaka Sugawara, Takahiro Kageyama, Junichi Ishikawa, Yoshie Sanayama, Kei Ikeda, Shunsuke Furuta, Shin-Ichiro Kagami, Arifumi Iwata, Koichi Hirose, Kotaro Suzuki, Osamu Ohara, Hiroshi Nakajima
Abstract
Radiographic contact of glioblastoma (GBM) tumors with the lateral ventricle and adjacent stem cell niche correlates with poor patient prognosis, but the cellular basis of this difference is unclear. Here, we reveal and functionally characterize distinct immune microenvironments that predominate in subtypes of GBM distinguished by proximity to the lateral ventricle. Mass cytometry analysis of IDH-wildtype human tumors identified elevated T cell checkpoint receptor expression and greater abundance of a specific CD32+CD44+HLA-DRhigh macrophage population in ventricle-contacting GBM. Multiple computational analysis approaches, phospho-specific cytometry, and focal resection of GBMs confirmed and extended these findings. Phospho-flow quantified cytokine-induced immune cell signaling in ventricle-contacting GBM revealing differential signaling between GBM subtypes. Subregion analysis within a given tumor supported initial findings and revealed intratumoral compartmentalization of T cell memory and exhaustion phenotypes within GBM subtypes. Collectively, these results characterize immunotherapeutically targetable features of macrophages and suppressed lymphocytes in glioblastomas defined by MRI-detectable lateral ventricle contact.
Authors
Todd Bartkowiak, Sierra M. Lima, Madeline J. Hayes, Akshitkumar M. Mistry, Asa A. Brockman, Justine Sinnaeve, Nalin Leelatian, Caroline E. Roe, Bret C. Mobley, Silky Chotai, Kyle D. Weaver, Reid C. Thompson, Lola B. Chambless, Rebecca A. Ihrie, Jonathan M. Irish
Abstract
T cells play an important role in acute kidney injury (AKI). Metabolic programming of T cells regulates their function, is a rapidly emerging field, and is unknown in AKI. We induced ischemic AKI in C57B6 mice and collected kidneys and spleens at multiple time points. T cells were isolated and analyzed by an immune-metabolic assay. Unbiased machine learning analyses identified a distinct T cell subset with reduced VDAC1 and mTOR expression in post-AKI kidneys. Ischemic kidneys showed higher expression of trimethylation of histone H3 lysine 27 (H3K27Me3) and glutaminase. Splenic T cells from post-AKI mice had higher expression of GLUT1, hexokinase II, and CPT1a. Human nonischemic and ischemic kidney tissue displayed similar findings to mouse kidneys. Given a convergent role for glutamine in T cell metabolic pathways and the availability of a relatively safe glutamine antagonist JHU083, effects on AKI were evaluated. JHU083 attenuated renal injury and reduced T cell activation and proliferation in ischemic and nephrotoxic AKI, whereas T cell-deficient mice were not protected by glutamine blockade. In vitro hypoxia demonstrated upregulation of glycolysis-related enzymes. T cells undergo metabolic reprogramming during AKI, and reconstitution of metabolism by targeting T cell glutamine pathway could be a promising novel therapeutic approach.
Authors
Kyungho Lee, Elizabeth A. Thompson, Sepideh Gharaie, Chirag H. Patel, Johanna T. Kurzhagen, Phillip M. Pierorazio, Lois J. Arend, Ajit G. Thomas, Sanjeev Noel, Barbara S. Slusher, Hamid Rabb
Abstract
cyclic GMP-AMP synthase (cGAS) is a DNA sensor and responsible for inducing an anti-tumor immune response. Recent studies reveal cGAS is frequently inhibited in cancer, and therapeutic targets to promote anti-tumor cGAS function remain elusive. SRC is a proto-oncogene tyrosine kinase and is expressed at elevated levels in numerous cancers. Here, we demonstrate that SRC expression in primary and metastatic bladder cancer negatively correlates with innate immune gene expression and immune cell infiltration. We determine that SRC restricts cGAS signaling in human cell lines through SRC small molecule inhibitors, depletion, and overexpression. cGAS and SRC interact in cells and in vitro, while SRC directly inhibits cGAS enzymatic activity and DNA binding in a kinase-dependent manner. SRC phosphorylates cGAS, and inhibition of cGAS Y248 phosphorylation partially reduces SRC inhibition. Collectively, our study demonstrates that cGAS anti-tumor signaling is hindered by the proto-oncogene SRC and describes how cancer-associated proteins can regulate the innate immune system.
Authors
William Dunker, Shivam A. Zaver, Jose Mario Bello Pineda, Cameron J. Howard, Robert K. Bradley, Joshua J. Woodward
Abstract
Respiratory syncytial virus (RSV) infection causes significant morbidity and mortality in infants, immunocompromised, and older individuals. There is an urgent need for effective antivirals and vaccines for high risk individuals. We used two complementary in vivo models to analyze RSV-associated human lung pathology and human immune correlates of protection. RSV infection resulted in widespread human lung epithelial damage, a pro-inflammatory innate immune response, and elicited a natural adaptive human immune response that conferred protective immunity. We demonstrated a key role for human T cells in controlling RSV infection. Specifically, primed human CD8+ T cells or CD4+ T cells effectively and independently control RSV replication in human lung tissue in the absence of an RSV-specific antibody response. These preclinical data support the development of RSV vaccines which also elicit effective T cell responses to improve RSV vaccine efficacy.
Authors
Chandrav De, Raymond J. Pickles, Wenbo Yao, Baolin Liao, Allison E. Boone, Mingyu Choi, Diana M. Battaglia, Frederic B. Askin, Jason K. Whitmire, Guido Silvestri, J. Victor Garcia, Angela Wahl
Abstract
Laryngotracheal stenosis (LTS) is pathologic fibrotic narrowing of the larynx and trachea characterized by hypermetabolic fibroblasts and CD4-mediated inflammation. However, the role of CD4 T-cells in promoting LTS fibrosis is unknown. The mechanistic target of rapamycin (mTOR) signaling pathways have been shown to regulate T-cell phenotype. Here we sought to investigate the influence of mTOR signaling in CD4 T-cells on LTS pathogenesis. In this study, human LTS specimens revealed an increased population of CD4-cells expressing the activated isoform of mTOR. In a murine LTS model, targeting mTOR with systemic sirolimus and a sirolimus-eluting airway stent reduced fibrosis and TH17-cells. Selective deletion of mTOR in CD4+-cells reduced TH17-cells and attenuated fibrosis, demonstrating CD4-cells’ pathologic role in LTS. Multispectral immunofluorescence of human LTS revealed increased TH17-cells. In-vitro, TH17-cells increased collagen-1 production by LTS fibroblasts, which was prevented with sirolimus pretreatment of TH17-cells. Collectively, mTOR signaling drives pathologic CD4 T-cell phenotypes in LTS, and targeting mTOR with sirolimus is effective at treating LTS through inhibition of pro-fibrotic TH17-cells. Finally, sirolimus may be delivered locally with a drug-eluting stent, transforming clinical therapy for LTS.
Authors
Kevin M. Motz, Ioan A. Lina, Idris Samad, Michael K. Murphy, Madhavi Duvvuri, Ruth J. Davis, Alexander Gelbard, Liam Chung, Yee Chan-Li, Samuel Collins, Jonathan D. Powell, Jennifer H. Elisseeff, Maureen R. Horton, Alexander T. Hillel
Abstract
Immune responses in people with multiple sclerosis (pwMS) on disease-modifying therapies (DMTs) have been of significant interest throughout the COVID-19 pandemic. Lymphocyte-targeting immunotherapies including anti-CD20 treatments and sphingosine-1-phosphate receptor (S1PR) modulators attenuate antibody responses after vaccination. Evaluation of cellular responses after vaccination is therefore of particular importance in these populations. In this study, we analysed CD4 and CD8 T cell functional responses to SARS-CoV-2 spike peptides in healthy controls and pwMS on five different DMTs by flow cytometry. Although pwMS on rituximab and fingolimod therapies had low antibody responses after both two and three vaccine doses, T cell responses in pwMS on rituximab were preserved after a third vaccination, even when an additional dose of rituximab was administered between vaccine doses two and three. PwMS taking fingolimod had low detectable T cell responses in peripheral blood. CD4 and CD8 T cell responses to SARS-CoV-2 variants of concern Delta and Omicron were lower than to the ancestral Wuhan-Hu-1 variant. Our results indicate the importance of assessing both cellular and humoral responses after vaccination and suggest that even in the absence of robust antibody responses vaccination can generate immune responses in pwMS.
Authors
Asia-Sophia Wolf, Anthony Ravussin, Marton König, Mathias H. Øverås, Guri Solum, Ingrid Fadum Kjønstad, Adity Chopra, Trygve Holmøy, Hanne F. Harbo, Silje Watterdal Syversen, Kristin Kaasen Jørgensen, Einar A. Høgestøl, John T. Vaage, Elisabeth G. Celius, Fridtjof Lund-Johansen, Ludvig A. Munthe, Gro Owren Nygaard, Siri Mjaaland
Abstract
Obesity-associated metabolic inflammation drives the development of insulin resistance and type 2 diabetes, notably through modulating innate and adaptive immune cells in metabolic organs. The nutrient sensor liver kinase B1 (LKB1) has recently been shown to control cellular metabolism and T cell priming functions of dendritic cells (DCs). Here, we report that hepatic DCs from high-fat diet (HFD)-fed obese mice display increased LKB1 phosphorylation and that LKB1 deficiency in DCs (CD11cΔLKB1) worsened HFD-driven hepatic steatosis and impaired glucose homeostasis. Loss of LKB1 in DCs was associated with increased expression of T helper 17-polarizing cytokines and accumulation of hepatic IL-17A+ T helper cells in HFD-fed mice. Importantly, IL-17A neutralization rescued metabolic perturbations in HFD-fed CD11cΔLKB1 mice. Mechanistically, deficiency of the canonical LKB1 target AMPK in HFD-fed CD11cΔAMPKα1 mice recapitulated neither the hepatic Th17 phenotype nor the disrupted metabolic homeostasis, suggesting the involvement of other and/or additional LKB1 downstream effectors. We indeed provide evidence that the control of Th17 responses by DCs via LKB1 is actually dependent on both AMPKalpha1 and AMPK-related salt-inducible kinase(s) signaling. Altogether, our data reveal a key role for LKB1 signaling in DCs in protection against obesity-induced metabolic dysfunctions by limiting hepatic Th17 responses.
Authors
Hendrik J.P. van der Zande, Eline C. Brombacher, Joost M. Lambooij, Leonard R. Pelgrom, Anna Zawistowska-Deniziak, Thiago A. Patente, Graham A. Heieis, Frank Otto, Arifa Ozir-Fazalalikhan, Maria Yazdanbakhsh, Bart Everts, Bruno Guigas
Abstract
Alloreactivity can drive autoimmune syndromes. After allogeneic hematopoietic stem cell transplantation (allo-HCT) chronic graft-versus-host disease (cGVHD), a B cell-mediated autoimmune-like syndrome, commonly occurs. Because donor-derived B cells continually develop under selective pressure from host alloantigens, aberrant B Cell Receptor (BCR)-activation and IgG production can emerge and contribute to cGVHD pathobiology. To better understand molecular programing of B cells under selective pressure of alloantigens, we performed scRNA-Seq analysis on high numbers of purified B cells from allo-HCT patients. An unsupervised analysis revealed 10 clusters, distinguishable by signature genes for maturation, activation and memory. We found striking transcriptional differences in the memory B cell compartment after allo-HCT compared to healthy or infected individuals. To identify intrinsic properties when B-cell tolerance is lost after allo-HCT, we then assessed clusters for differentially expressed genes (DEGs) between patients with vs. without autoimmune-like manifestations (Active cGVHD vs. No cGVHD, respectively). DEGs were found in Active cGVHD in both naive and BCR-activated clusters, suggesting functional diversity. Some DEGs were also differentially expressed across most clusters, suggesting common molecular programs that may promote B cell plasticity. Our study of human allo-HCT and cGVHD provides new understanding of B-cell memory in the face of chronic alloantigen stimulation.
Authors
Jonathan C. Poe, Jiyuan Fang, Dadong Zhang, Marissa R. Lee, Rachel A. DiCioccio, Hsuan Su, Xiaodi Qin, Jennifer Y. Zhang, Jonathan Visentin, Sonali J. Bracken, Vincent T. Ho, Kathy S. Wang, Jeremy J. Rose, Steven Z. Pavletic, Frances T. Hakim, Wei Jia, Amy N. Suthers, Itaevia M. Curry-Chisolm, Mitchell E. Horwitz, David A. Rizzieri, William C. McManigle, Nelson J. Chao, Adela R. Cardones, Jichun Xie, Kouros Owzar, Stefanie Sarantopoulos
Abstract
Fibroblastic reticular cells (FRCs) play important roles in tolerance by producing laminin α4 (Lama4) and altering lymph node (LN) structure and function. The present study revealed the specific roles of extracellular matrix Lama4 in regulating LN conduits using FRC-specific KO mouse strains. FRC-derived Lama4 maintained conduit fiber integrity, as its depletion altered conduit morphology and structure and reduced homeostatic conduit flow. Lama4 regulated the lymphotoxin β receptor (LTβR) pathway, which is critical for conduit and LN integrity. Depleting LTβR in FRCs further reduced conduits and impaired reticular fibers. Lama4 was indispensable for FRC generation and survival, as FRCs lacking Lama4 displayed reduced proliferation but upregulated senescence and apoptosis. During acute immunization, FRC Lama4 deficiency increased antigen flow through conduits. Importantly, adoptive transfer of WT FRCs to FRC Lama4–deficient mice rescued conduit structure, ameliorated Treg and chemokine distribution, and restored transplant allograft acceptance, which were all impaired by FRC Lama4 depletion. Single-cell RNA sequencing analysis of LN stromal cells indicated that the laminin and collagen signaling pathways linked crosstalk among FRC subsets and endothelial cells. This study demonstrated that FRC Lama4 is responsible for maintaining conduits by FRCs and can be harnessed to potentiate FRC-based immunomodulation.
Authors
Lushen Li, Long Wu, Allison Kensiski, Jing Zhao, Marina W. Shirkey, Yang Song, Wenji Piao, Tianshu Zhang, Zhongcheng Mei, Samuel J. Gavzy, Bing Ma, Vikas Saxena, Young S. Lee, Yanbao Xiong, Xiaofei Li, Xiaoxuan Fan, Reza Abdi, Jonathan S. Bromberg
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