Autoimmunity
Abstract
Regulatory T (Treg) cells require Foxp3 expression and induction of a specific DNA hypomethylation signature during development, after which Treg cells persist as a self-renewing population that regulates immune system activation. Whether maintenance DNA methylation is required for Treg cell lineage development and stability and how methylation patterns are maintained during lineage self-renewal remain unclear. Here, we demonstrate that the epigenetic regulator Uhrf1 is essential for maintenance of methyl-DNA marks that stabilize Treg cellular identity by repressing effector T cell transcriptional programs. Constitutive and induced deficiency of Uhrf1 within Foxp3+ cells resulted in global yet non-uniform loss of DNA methylation, derepression of inflammatory transcriptional programs, destabilization of the Treg cell lineage, and spontaneous inflammation. These findings support a paradigm in which maintenance DNA methylation is required in distinct regions of the Treg cell genome for both lineage establishment and stability of identity and suppressive function.
Authors
Kathryn A. Helmin, Luisa Morales-Nebreda, Manuel A. Torres Acosta, Kishore R. Anekalla, Shang-Yang Chen, Hiam Abdala-Valencia, Yuliya Politanska, Paul Cheresh, Mahzad Akbarpour, Elizabeth M. Steinert, Samuel E. Weinberg, Benjamin D. Singer
Abstract
The transcription factor interferon regulatory factor 5 (IRF5) is a central mediator of innate and adaptive immunity. Genetic variations within IRF5 associate with risk of systemic lupus erythematosus (SLE) and mice lacking Irf5 are protected from lupus onset and severity, but how IRF5 functions in the context of SLE disease progression remains unclear. Using the NZB/W F1 model of murine lupus, we show that murine Irf5 becomes hyper-activated before clinical onset. In SLE patients, IRF5 hyper-activation correlated with dsDNA titers. To test whether IRF5 hyper-activation is a targetable function, we developed novel inhibitors that are cell permeable, non-toxic and selectively bind to the inactive IRF5 monomer. Preclinical treatment of NZB/W F1 mice with inhibitor attenuated lupus pathology by reducing serum ANA, dsDNA titers and the number of circulating plasma cells, which alleviated kidney pathology and improved survival. Clinical treatment of MRL/lpr and pristane-induced mice with inhibitor led to significant reductions in dsDNA levels and improved survival. In ex vivo human studies, the inhibitor blocked SLE serum-induced IRF5 activation in healthy immune cells and reversed basal IRF5 hyper-activation in SLE immune cells. Altogether, this study provides the first in vivo clinical support for treating SLE patients with an IRF5 inhibitor.
Authors
Su Song, Saurav De, Victoria Nelson, Samin Chopra, Margaret LaPan, Kyle Kampta, Shan Sun, Mingzhu He, Cherrie D. Thompson, Dan Li, Tiffany Shih, Natalie Tan, Yousef Al-Abed, Eugenio Capitle, Cynthia Aranow, Meggan Mackay, William L. Clapp, Betsy J. Barnes
Abstract
Psoriasis is a severe disease associated with the disturbance of metabolism and inflammation, but the molecular mechanisms underlying these aspects of psoriasis pathology are poorly understood. Here, we report that glutaminase 1–mediated (GLS1-mediated) glutaminolysis was aberrantly activated in patients with psoriasis and in psoriasis-like mouse models, which promoted Th17 and γδ T17 (IL-17A–producing γδ T) cell differentiation through enhancement of histone H3 acetylation of the Il17a promoter, thereby contributing to the immune imbalance and development of psoriasis. We further demonstrate that mucosa-associated lymphoid tissue lymphoma translocation protein 1 (MALT1) protease was constitutively active in psoriatic CD4+ and γδ T cells, thereby supporting GLS1 expression by stabilizing c-Jun, which directly binds to the GLS1 promoter region. Blocking the activity of either GLS1 or MALT1 protease resolved Th17 and γδ T17 cell differentiation and epidermal hyperplasia in the psoriasis-like mouse models. Finally, IL-17A enhanced GLS1 expression via the MALT1/cJun pathway in keratinocytes, resulting in hyperproliferation of and chemokine production by keratinocytes. Our findings identify the role of the MALT1/cJun/GLS1/glutaminolysis/H3 acetylation/T17 axis in psoriasis pathogenesis and reveal potential therapeutic targets for this disease.
Authors
Xichun Xia, Guangchao Cao, Guodong Sun, Leqing Zhu, Yixia Tian, Yueqi Song, Chengbin Guo, Xiao Wang, Jingxiang Zhong, Wei Zhou, Peng Li, Hua Zhang, Jianlei Hao, Zhizhong Li, Liehua Deng, Zhinan Yin, Yunfei Gao
Abstract
Desmoglein 3 chimeric autoantibody receptor T-cells (DSG3-CAART) expressing the pemphigus vulgaris (PV) autoantigen DSG3, fused to CD137-CD3ζ signaling domains, represent a precision cellular immunotherapy approach for antigen-specific B-cell depletion. Here, we present definitive preclinical studies enabling a first-in-human trial of DSG3-CAART for mucosal PV. DSG3-CAART specifically lysed human anti-DSG3 B-cells from PV patients and demonstrated activity consistent with a threshold dose in vivo, resulting in decreased target cell burden, decreased serum and tissue-bound autoantibodies, and increased DSG3-CAART engraftment. In a PV active immune model with physiologic anti-DSG3 IgG levels, DSG3-CAART inhibited antibody responses against pathogenic DSG3 epitopes and autoantibody binding to epithelial tissues, leading to clinical and histologic resolution of blisters. DSG3 autoantibodies stimulate DSG3-CAART IFNγ secretion and homotypic clustering, consistent with an activated phenotype. Toxicology screens using primary human cells and high-throughput membrane proteome arrays did not identify off-target cytotoxic interactions. These preclinical data guided the trial design for DSG3-CAART and may help inform CAART preclinical development for other antibody-mediated diseases.
Authors
Jinmin Lee, Daniel K. Lundgren, Xuming Mao, Silvio Manfredo-Vieira, Selene Nunez-Cruz, Erik F. Williams, Charles-Antoine Assenmacher, Enrico Radaelli, Sangwook Oh, Baomei Wang, Christoph T. Ellebrecht, Joseph A. Fraietta, Michael C. Miloneǂ, Aimee S. Payne
Abstract
FOXP3+CD4+ regulatory T cells (Tregs) are critical for immune homeostasis and respond to local tissue cues, which control their stability and function. We explored here whether DEL-1, which, like Tregs, increases during resolution of inflammation, promotes Treg responses. DEL-1 enhanced Treg numbers and function at barrier sites (oral and lung mucosa). The underlying mechanism was dissected using mice lacking DEL-1 or expressing a point mutant thereof, or mice with T cell-specific deletion of the transcription factor RUNX1, identified by RNA-seq analysis of the DEL-1-induced Treg transcriptome. Specifically, through interaction with αvβ3-integrin, DEL-1 promoted induction of RUNX1-dependent FOXP3 expression and conferred stability of FOXP3 expression upon Treg restimulation in the absence of exogenous TGFβ1. Consistently, DEL-1 enhanced the demethylation of the Treg-specific demethylated region (TSDR) in the mouse Foxp3 gene and the suppressive function of sorted induced Tregs. Similarly, DEL-1 increased RUNX1 and FOXP3 expression in human conventional T cells promoting their conversion into induced Tregs with increased TSDR demethylation, enhanced stability and suppressive activity. We thus uncovered a DEL-1-αvβ3-RUNX1 axis that promotes Treg responses at barrier sites and offers novel therapeutic options for modulating inflammatory/autoimmune disorders.
Authors
Xiaofei Li, Alessandra Colamatteo, Lydia Kalafati, Tetsuhiro Kajikawa, Hui Wang, Jong-Hyung Lim, Khalil Bdeir, Kyoung-Jin Chung, Xiang Yu, Clorinda Fusco, Antonio Porcellini, Salvatore De Simone, Giuseppe Matarese, Triantafyllos Chavakis, Veronica De Rosa, George Hajishengallis
Abstract
Clinical trials are currently testing whether induction of MHC-haploidentical mixed chimerism (Haplo-MC) induces organ transplantation tolerance. Whether Haplo-MC can be used to treat established autoimmune diseases remains unknown. Here, we show that established autoimmunity in euthymic and adult-thymectomized NOD (H-2g7) mice was cured by induction of Haplo-MC under a non-myeloablative anti-thymocyte globulin-based conditioning regimen and infusion of CD4+ T-depleted hematopoietic graft from H-2b/g7 F1 donors that express autoimmune-resistant H-2b or from H-2s/g7 F1 donors that express autoimmune susceptible H-2s. The cure was associated with enhanced thymic negative selection, increased thymic Treg (tTreg) production, and anergy or exhaustion of residual host-type autoreactive T cells in the periphery. The peripheral tolerance was accompanied with expansion of donor- and host-type CD62L1Helios+ tTreg as well as host-type Helios-Nrp1+ peripheral Treg (pTreg) and PD-L1hi plasmacytoid DCs (pDC). Depletion of donor- or host-type Treg cells led to reduction of host-type PD-L1hi pDCs and recurrence of autoimmunity; whereas PD-L1 deficiency in host-type DCs led to reduction of host-type pDCs and Helios-Nrp1+ pTreg cells. Thus, induction of Haplo-MC re-established both central and peripheral tolerance through mechanisms that depend on allo-MHC+ donor-type DC, PD-L1hi host-type DCs, and the generation and persistence of donor and host-type tTreg and pTreg cells.
Authors
Yuqing Liu, Xiaoqi Wang, Yongping Zhu, Mingfeng Zhang, Ubaydah Nasri, Sharne S. Sun, Stephen J. Forman, Arthur D. Riggs, Zhang Xi, Defu Zeng
Abstract
How T cells integrate environmental cues into signals that limit the magnitude and length of immune responses is poorly understood. Here, we provide data that demonstrates that B55ß, a regulatory subunit of the phosphatase PP2A, represents a molecular link between cytokine concentration and apoptosis in activated CD8 T cells. Through the modulation of AKT, B55ß induced the expression of the pro-apoptotic molecule Hrk in response to cytokine withdrawal. Accordingly, B55ß and Hrk were both required for in vivo and in vitro contraction of activated CD8 lymphocytes. We show that this process plays a role during clonal contraction, establishment of immune memory, and preservation of peripheral tolerance. This regulatory pathway may represent an unexplored opportunity to end unwanted immune responses, or to promote immune memory.
Authors
Noé Rodríguez-Rodríguez, Iris K. Madera-Salcedo, J. Alejandro Cisneros-Segura, H. Benjamin García-González, Sokratis A. Apostolidis, Abril Saint-Martin, Marcela Esquivel-Velázquez, Tran Nguyen, Dámaris P. Romero-Rodríguez, George C. Tsokos, Jorge Alcocer-Varela, Florencia Rosetti, Jose C. Crispin
Abstract
Idiopathic inflammatory myopathies (IIM) involve chronic inflammation of skeletal muscle and subsequent muscle degeneration due to an uncontrolled autoimmune response; however, the mechanisms leading to pathogenesis are not well understood. A compromised sarcolemmal repair process could promote an aberrant exposure of intramuscular antigens with the subsequent initiation of an inflammatory response that contributes to IIM. Using an adoptive transfer mouse model of IIM, we show that sarcolemmal repair is significantly compromised in distal skeletal muscle in the absence of inflammation. We identified autoantibodies against TRIM72 (also known as MG53), a muscle-enriched membrane repair protein, in IIM patient sera and in our mouse model of IIM by ELISA. We found that patient sera with elevated levels of TRIM72 autoantibodies suppress sarcolemmal resealing in healthy skeletal muscle, and depletion of TRIM72 antibodies from these same serum samples rescues sarcolemmal repair capacity. Autoantibodies targeting TRIM72 lead to skeletal muscle fibers with compromised membrane barrier function, providing a continuous source of autoantigens to promote autoimmunity and further amplifying humoral responses. These findings reveal a potential pathogenic mechanism that acts as a feedback loop contributing to the progression of IIM.
Authors
Kevin E. McElhanon, Nicholas Young, Jeffrey Hampton, Brian J. Paleo, Thomas A. Kwiatkowski, Eric X Beck, Ana Capati, Kyle Jablonski, Travis Gurney, Miguel A. Lopez Perez, Rohit Aggarwal, Chester V. Oddis, Wael N. Jarjour, Noah Weisleder
Abstract
BACKGROUND. Idiopathic CD4 lymphopenia (ICL) is defined by persistent low CD4 counts (<300 cells/µL) in the absence of a causal infection or immune deficiency and can manifest with opportunistic infections. Approximately 30% of ICL patients develop autoimmune disease. The prevalence and breadth of their autoantibodies, however, and their potential contribution to pathogenesis of ICL remain unclear. METHODS. We hybridized 35 and 51 ICL patients’ sera to a 9,000 human proteome array and to a 128 known autoantigens array, respectively. Using a flow-based method, we characterized the presence of anti-lymphocyte Ab in the whole cohort of 72 patients, as well as the Ab functional capability of inducing antibody-dependent cell-mediated cytotoxicity (ADCC), complement deposition, and complement dependent cytotoxicity (CDC). We tested ex vivo the activation of the classical complement pathway on ICL CD4 T cells. RESULTS. All ICL patients had multitude of autoantibodies mostly directed against private (not shared) targets and unrelated quantitatively or qualitatively to the patients’ autoimmune disease status. The targets included lymphocyte intracellular and membrane antigens, confirmed by the detection by flow of IgM and IgG (mostly IgG1 and IgG4) anti-CD4 cell Ab in 50% of the patients with half of these cases triggering lysis of CD4 T cells. We also detected in vivo classical complement activation on CD4 T cells in 14% of the whole cohort. CONCLUSION. Our data demonstrate a high prevalence of autoantibodies in ICL, some of which are specific against CD4 T cells, may contribute to pathogenesis and may represent a potential novel therapeutic target.
Authors
Ainhoa Perez-Diez, Chun-Shu Wong, Xiangdong Liu, Harry A. Mystakelis, Jian song, Yong Lu, Virginia Sheikh, Jeffrey S. Bourgeois, Andrea Lisco, Elizabeth Laidlaw, Cornelia D. Cudrici, Chengsong Zhu, Quan-Zhen Li, Alexandra F. Freeman, Peter R. Williamson, Megan V. Anderson, Gregg Roby, John S. Tsang, Richard M. Siegel, Irini Sereti
Abstract
TGFβ is a master regulator of fibrosis, driving the differentiation of fibroblasts into apoptosis resistant myofibroblasts and sustaining the production of extracellular matrix (ECM) components. Here, we identify the nuclear lncRNA H19X as a master regulator of TGFβ-driven tissue fibrosis. H19X was consistently upregulated in a wide variety of human fibrotic tissues and diseases and was strongly induced by TGFβ, particularly in fibroblasts and fibroblast-related cells. Functional experiments following H19X silencing revealed that H19X is an obligatory factor for the TGFβ-induced ECM synthesis as well as differentiation and survival of ECM-producing myofibroblasts. We showed that H19X regulates DDIT4L gene expression, specifically interacting with a region upstream of DDIT4L gene and changing the chromatin accessibility of a DDIT4L enhancer. These events resulted in transcriptional repression of DDIT4L and, in turn, in increased collagen expression and fibrosis. Our results shed light on key effectors of the TGFβ-induced ECM remodeling and fibrosis.
Authors
Elena Pachera, Shervin Assassi, Gloria A. Salazar, Mara Stellato, Florian Renoux, Adam Wunderlin, Przemyslaw Blyszczuk, Robert Lafyatis, Fina Kurreeman, Jeska de Vries-Bouwstra, Tobias Messemaker, Carol A. Feghali-Bostwick, Gerhard Rogler, Wouter T. van Haaften, Gerard Dijkstra, Fiona Oakley, Maurizio Calcagni, Janine Schniering, Britta Maurer, Jörg H.W. Distler, Gabriela Kania, Mojca Frank-Bertoncelj, Oliver Distler
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ISSN: 0021-9738 (print), 1558-8238 (online)