Protective responses against pathogens require a rapid mobilization of resting neutrophils and the timely removal of activated ones. Neutrophils are exceptionally short-lived leukocytes, yet it remains unclear whether the lifespan of pathogen-engaged neutrophils is regulated differently from that in the circulating steady-state pool. Here, we have found that under homeostatic conditions, the mRNA-destabilizing protein tristetraprolin (TTP) regulates apoptosis and the numbers of activated infiltrating murine neutrophils but not neutrophil cellularity. Activated TTP-deficient neutrophils exhibited decreased apoptosis and enhanced accumulation at the infection site. In the context of myeloid-specific deletion of
Florian Ebner, Vitaly Sedlyarov, Saren Tasciyan, Masa Ivin, Franz Kratochvill, Nina Gratz, Lukas Kenner, Andreas Villunger, Michael Sixt, Pavel Kovarik
Ajitha Thanabalasuriar, Bas G.J. Surewaard, Michelle E. Willson, Arpan S. Neupane, Charles K. Stover, Paul Warrener, George Wilson, Ashley E. Keller, Bret R. Sellman, Antonio DiGiandomenico, Paul Kubes
A large proportion of human T cells are autoreactive to group 1 CD1 proteins, which include CD1a, CD1b, and CD1c. However, the physiological role of the CD1 proteins remains poorly defined. Here, we have generated a double-transgenic mouse model that expresses human CD1b and CD1c molecules (hCD1Tg) as well as a CD1b-autoreactive TCR (HJ1Tg) in the ApoE-deficient background (hCD1Tg HJ1Tg
Sreya Bagchi, Ying He, Hong Zhang, Liang Cao, Ildiko Van Rhijn, D. Branch Moody, Johann E. Gudjonsson, Chyung-Ru Wang
Inflammatory bowel disease (IBD) is characterized by dysregulation in both cytokines and responses to intestinal microbes, and proper regulation of pattern recognition receptor (PRR) signaling is critical for intestinal immune homeostasis. Altered functions for the IBD risk locus containing rs7554511, which encompasses the
Jie Yan, Matija Hedl, Clara Abraham
Tissue-resident immune cells play a key role in local and systemic immune responses. The liver, in particular, hosts a large number of invariant natural killer T (iNKT) cells, which are involved in diverse immune responses. However, the mechanisms that regulate survival and homeostasis of liver iNKT cells are poorly defined. Here we have found that liver iNKT cells constitutively express the costimulatory TNF superfamily receptor OX40 and that OX40 stimulation results in massive pyroptotic death of iNKT cells, characterized by the release of potent proinflammatory cytokines that induce liver injury. This OX40/NKT pyroptosis pathway also plays a key role in concanavalin A–induced murine hepatitis. Mechanistically, we demonstrated that liver iNKT cells express high levels of caspase 1 and that OX40 stimulation activates caspase 1 via TNF receptor–associated factor 6–mediated recruitment of the paracaspase MALT1. We also found that activation of caspase 1 in iNKT cells results in processing of pro–IL-1β to mature IL-1β as well as cleavage of the pyroptotic protein gasdermin D, which generates a membrane pore–forming fragment to produce pyroptotic cell death. Thus, our study has identified OX40 as a death receptor for iNKT cells and uncovered a molecular mechanism of pyroptotic cell death. These findings may have important clinical implications in the development of OX40-directed therapies.
Peixiang Lan, Yihui Fan, Yue Zhao, Xiaohua Lou, Howard P. Monsour, Xiaolong Zhang, Yongwon Choi, Yaling Dou, Naoto Ishii, Rafik M. Ghobrial, Xiang Xiao, Xian Chang Li
Proinflammatory cytokine overproduction and excessive cell death, coupled with impaired clearance of apoptotic cells, have been implicated as causes of failure to resolve gut inflammation in inflammatory bowel diseases. Here we have found that dendritic cells expressing the apoptotic cell–recognizing receptor CD300f play a crucial role in regulating gut inflammatory responses in a murine model of colonic inflammation. CD300f-deficient mice failed to resolve dextran sulfate sodium–induced colonic inflammation as a result of defects in dendritic cell function that were associated with abnormal accumulation of apoptotic cells in the gut. CD300f-deficient dendritic cells displayed hyperactive phagocytosis of apoptotic cells, which stimulated excessive TNF-α secretion predominantly from dendritic cells. This, in turn, induced secondary IFN-γ overproduction by colonic T cells, leading to prolonged gut inflammation. Our data highlight a previously unappreciated role for dendritic cells in controlling gut homeostasis and show that CD300f-dependent regulation of apoptotic cell uptake is essential for suppressing overactive dendritic cell–mediated inflammatory responses, thereby controlling the development of chronic gut inflammation.
Ha-Na Lee, Linjie Tian, Nicolas Bouladoux, Jacquice Davis, Mariam Quinones, Yasmine Belkaid, John E. Coligan, Konrad Krzewski
Inborn errors of DNA repair or replication underlie a variety of clinical phenotypes. We studied 5 patients from 4 kindreds, all of whom displayed intrauterine growth retardation, chronic neutropenia, and NK cell deficiency. Four of the 5 patients also had postnatal growth retardation. The association of neutropenia and NK cell deficiency, which is unusual among primary immunodeficiencies and bone marrow failures, was due to a blockade in the bone marrow and was mildly symptomatic. We discovered compound heterozygous rare mutations in Go-Ichi-Ni-San (GINS) complex subunit 1 (
Julien Cottineau, Molly C. Kottemann, Francis P. Lach, Young-Hoon Kang, Frédéric Vély, Elissa K. Deenick, Tomi Lazarov, Laure Gineau, Yi Wang, Andrea Farina, Marie Chansel, Lazaro Lorenzo, Christelle Piperoglou, Cindy S. Ma, Patrick Nitschke, Aziz Belkadi, Yuval Itan, Bertrand Boisson, Fabienne Jabot-Hanin, Capucine Picard, Jacinta Bustamante, Céline Eidenschenk, Soraya Boucherit, Nathalie Aladjidi, Didier Lacombe, Pascal Barat, Waseem Qasim, Jane A. Hurst, Andrew J. Pollard, Holm H. Uhlig, Claire Fieschi, Jean Michon, Vladimir P. Bermudez, Laurent Abel, Jean-Pierre de Villartay, Frédéric Geissmann, Stuart G. Tangye, Jerard Hurwitz, Eric Vivier, Jean-Laurent Casanova, Agata Smogorzewska, Emmanuelle Jouanguy
Programmed death ligand-1 (PD-L1) interacts with programmed death-1 (PD-1) and the immunostimulatory molecule CD80 and functions as a checkpoint to regulate immune responses. The interaction of PD-L1 with CD80 alone has been shown to exacerbate the severity of graft-versus-host disease (GVHD), whereas costimulation of CD80 and PD-1 ameliorates GVHD. Here we have demonstrated that temporary depletion of donor CD4+ T cells early after hematopoietic cell transplantation effectively prevents GVHD while preserving strong graft-versus-leukemia (GVL) effects in allogeneic and xenogeneic murine GVHD models. Depletion of donor CD4+ T cells increased serum IFN-γ but reduced IL-2 concentrations, leading to upregulation of PD-L1 expression by recipient tissues and donor CD8+ T cells. In GVHD target tissues, the interactions of PD-L1 with PD-1 on donor CD8+ T cells cause anergy, exhaustion, and apoptosis, thereby preventing GVHD. In lymphoid tissues, the interactions of PD-L1 with CD80 augment CD8+ T cell expansion without increasing anergy, exhaustion, or apoptosis, resulting in strong GVL effects. These results indicate that the outcome of PD-L1–mediated signaling in CD8+ T cells depends on the presence or absence of CD4+ T cells, the nature of the interacting receptor expressed by CD8+ T cells, and the tissue environment in which the signaling occurs.
Xiong Ni, Qingxiao Song, Kaniel Cassady, Ruishu Deng, Hua Jin, Mingfeng Zhang, Haidong Dong, Stephen Forman, Paul J. Martin, Yuan-Zhong Chen, Jianmin Wang, Defu Zeng
The growth factor receptor Kit is involved in hematopoietic and nonhematopoietic development. Mice bearing
Pierre Cunin, Loka R. Penke, Jonathan N. Thon, Paul A. Monach, Tatiana Jones, Margaret H. Chang, Mary M. Chen, Imene Melki, Steve Lacroix, Yoichiro Iwakura, Jerry Ware, Michael F. Gurish, Joseph E. Italiano, Eric Boilard, Peter A. Nigrovic
Acute graft-versus-host disease (aGVHD) is the most common complication for patients undergoing allogeneic stem cell transplantation. Despite extremely aggressive therapy targeting donor T cells, patients with grade III or greater aGVHD of the lower GI tract, who do not respond to therapy with corticosteroids, have a dismal prognosis. Thus, efforts to improve understanding of the function of local immune and non-immune cells in regulating the inflammatory process in the GI tract during aGVHD are needed. Here, we demonstrate, using murine models of allogeneic BMT, that type 2 innate lymphoid cells (ILC2s) in the lower GI tract are sensitive to conditioning therapy and show very limited ability to repopulate from donor bone marrow. Infusion of donor ILC2s was effective in reducing the lethality of aGVHD and in treating lower GI tract disease. ILC2 infusion was associated with reduced donor proinflammatory Th1 and Th17 cells, accumulation of donor myeloid-derived suppressor cells (MDSCs) mediated by ILC2 production of IL-13, improved GI tract barrier function, and a preserved graft-versus-leukemia (GVL) response. Collectively, these findings suggest that infusion of donor ILC2s to restore gastrointestinal tract homeostasis may improve treatment of severe lower GI tract aGVHD.
Danny W. Bruce, Heather E. Stefanski, Benjamin G. Vincent, Trisha A. Dant, Shannon Reisdorf, Hemamalini Bommiasamy, David A. Serody, Justin E. Wilson, Karen P. McKinnon, Warren D. Shlomchik, Paul M. Armistead, Jenny P.Y. Ting, John T. Woosley, Bruce R. Blazar, Dietmar M.W. Zaiss, Andrew N.J. McKenzie, James M. Coghill, Jonathan S. Serody
Mature B cell pools retain a substantial proportion of polyreactive and self-reactive clonotypes, suggesting that activation checkpoints exist to reduce the initiation of autoreactive B cell responses. Here, we have described a relationship among the B cell receptor (BCR), TLR9, and cytokine signals that regulate B cell responses to DNA-containing antigens. In both mouse and human B cells, BCR ligands that deliver a TLR9 agonist induce an initial proliferative burst that is followed by apoptotic death. The latter mechanism involves p38-dependent G1 cell-cycle arrest and subsequent intrinsic mitochondrial apoptosis and is shared by all preimmune murine B cell subsets and CD27– human B cells. Survival or costimulatory signals rescue B cells from this fate, but the outcome varies depending on the signals involved. B lymphocyte stimulator (BLyS) engenders survival and antibody secretion, whereas CD40 costimulation with IL-21 or IFN-γ promotes a T-bet+ B cell phenotype. Finally, in vivo immunization studies revealed that when protein antigens are conjugated with DNA, the humoral immune response is blunted and acquires features associated with T-bet+ B cell differentiation. We propose that this mechanism integrating BCR, TLR9, and cytokine signals provides a peripheral checkpoint for DNA-containing antigens that, if circumvented by survival and differentiative cues, yields B cells with the autoimmune-associated T-bet+ phenotype.
Vishal J. Sindhava, Michael A. Oropallo, Krishna Moody, Martin Naradikian, Lauren E. Higdon, Lin Zhou, Arpita Myles, Nathaniel Green, Kerstin Nündel, William Stohl, Amanda M. Schmidt, Wei Cao, Stephanie Dorta-Estremera, Taku Kambayashi, Ann Marshak-Rothstein, Michael P. Cancro
In transplantation, there is a critical need for noninvasive biomarker platforms for monitoring immunologic rejection. We hypothesized that transplanted tissues release donor-specific exosomes into recipient circulation and that the quantitation and profiling of donor intra-exosomal cargoes may constitute a biomarker platform for monitoring rejection. Here, we have tested this hypothesis in a human-into-mouse xenogeneic islet transplant model and validated the concept in clinical settings of islet and renal transplantation. In the xenogeneic model, we quantified islet transplant exosomes in recipient blood over long-term follow-up using anti-HLA antibody, which was detectable only in xenoislet recipients of human islets. Transplant islet exosomes were purified using anti-HLA antibody–conjugated beads, and their cargoes contained the islet endocrine hormone markers insulin, glucagon, and somatostatin. Rejection led to a marked decrease in transplant islet exosome signal along with distinct changes in exosomal microRNA and proteomic profiles prior to appearance of hyperglycemia. In the clinical settings of islet and renal transplantation, donor exosomes with respective tissue specificity for islet β cells and renal epithelial cells were reliably characterized in recipient plasma over follow-up periods of up to 5 years. Collectively, these findings demonstrate the biomarker potential of transplant exosome characterization for providing a noninvasive window into the conditional state of transplant tissue.
Prashanth Vallabhajosyula, Laxminarayana Korutla, Andreas Habertheuer, Ming Yu, Susan Rostami, Chao-Xing Yuan, Sanjana Reddy, Chengyang Liu, Varun Korutla, Brigitte Koeberlein, Jennifer Trofe-Clark, Michael R. Rickels, Ali Naji
Alloimmune T cell responses induce graft-versus-host disease (GVHD), a serious complication of allogeneic bone marrow transplantation (allo-BMT). Although Notch signaling mediated by Delta-like 1/4 (DLL1/4) Notch ligands has emerged as a major regulator of GVHD pathogenesis, little is known about the timing of essential Notch signals and the cellular source of Notch ligands after allo-BMT. Here, we have shown that critical DLL1/4-mediated Notch signals are delivered to donor T cells during a short 48-hour window after transplantation in a mouse allo-BMT model. Stromal, but not hematopoietic, cells were the essential source of Notch ligands during in vivo priming of alloreactive T cells. GVHD could be prevented by selective inactivation of
Jooho Chung, Christen L. Ebens, Eric Perkey, Vedran Radojcic, Ute Koch, Leonardo Scarpellino, Alexander Tong, Frederick Allen, Sherri Wood, Jiane Feng, Ann Friedman, David Granadier, Ivy T. Tran, Qian Chai, Lucas Onder, Minhong Yan, Pavan Reddy, Bruce R. Blazar, Alex Y. Huang, Todd V. Brennan, D. Keith Bishop, Burkhard Ludewig, Christian W. Siebel, Freddy Radtke, Sanjiv A. Luther, Ivan Maillard
Mutations in the isocitrate dehydrogenase genes
Gary Kohanbash, Diego A. Carrera, Shruti Shrivastav, Brian J. Ahn, Naznin Jahan, Tali Mazor, Zinal S. Chheda, Kira M. Downey, Payal B. Watchmaker, Casey Beppler, Rolf Warta, Nduka A. Amankulor, Christel Herold-Mende, Joseph F. Costello, Hideho Okada
Moesin is a member of the ezrin-radixin-moesin (ERM) family of proteins that are important for organizing membrane domains and receptor signaling and regulating the migration of effector T cells. Whether moesin plays any role during the generation of TGF-β–induced Tregs (iTregs) is unknown. Here, we have discovered that moesin is translationally regulated by TGF-β and is also required for optimal TGF-β signaling that promotes efficient development of iTregs. Loss of moesin impaired the development and function of both peripherally derived iTregs and in vitro–induced Tregs. Mechanistically, we identified an interaction between moesin and TGF-β receptor II (TβRII) that allows moesin to control the surface abundance and stability of TβRI and TβRII. We also found that moesin is required for iTreg conversion in the tumor microenvironment, and the deletion of moesin from recipient mice supported the rapid expansion of adoptively transferred CD8+ T cells against melanoma. Our study establishes moesin as an important regulator of the surface abundance and stability of TβRII and identifies moesin’s role in facilitating the efficient generation of iTregs. It also provides an advancement to our understanding about the role of the ERM proteins in regulating signal transduction pathways and suggests that modulation of moesin is a potential therapeutic target for Treg-related immune disorders.
Ephraim A. Ansa-Addo, Yongliang Zhang, Yi Yang, George S. Hussey, Breege V. Howley, Mohammad Salem, Brian Riesenberg, Shaoli Sun, Don C. Rockey, Serhan Karvar, Philip H. Howe, Bei Liu, Zihai Li
Vaccines targeting glycan structures at the surface of pathogenic microbes must overcome the inherent T cell–independent nature of immune responses against glycans. Carbohydrate conjugate vaccines achieve this by coupling bacterial polysaccharides to a carrier protein that recruits heterologous CD4 T cells to help B cell maturation. Yet they most often produce low- to medium-affinity immune responses of limited duration in immunologically fit individuals and disappointing results in the elderly and immunocompromised patients. Here, we hypothesized that these limitations result from suboptimal T cell help. To produce the next generation of more efficacious conjugate vaccines, we have explored a synthetic design aimed at focusing both B cell and T cell recognition to a single short glycan displayed at the surface of a virus-like particle. We tested and established the proof of concept of this approach for 2 serotypes of
Zinaida Polonskaya, Shenglou Deng, Anita Sarkar, Lisa Kain, Marta Comellas-Aragones, Craig S. McKay, Katarzyna Kaczanowska, Marie Holt, Ryan McBride, Valle Palomo, Kevin M. Self, Seth Taylor, Adriana Irimia, Sanjay R. Mehta, Jennifer M. Dan, Matthew Brigger, Shane Crotty, Stephen P. Schoenberger, James C. Paulson, Ian A. Wilson, Paul B. Savage, M.G. Finn, Luc Teyton
The antiviral restriction factor IFN-induced transmembrane protein 3 (IFITM3) inhibits cell entry of a number of viruses, and genetic diversity within
Maria A. Stacey, Simon Clare, Mathew Clement, Morgan Marsden, Juneid Abdul-Karim, Leanne Kane, Katherine Harcourt, Cordelia Brandt, Ceri A. Fielding, Sarah E. Smith, Rachael S. Wash, Silvia Gimeno Brias, Gabrielle Stack, George Notley, Emma L. Cambridge, Christopher Isherwood, Anneliese O. Speak, Zoë Johnson, Walter Ferlin, Simon A. Jones, Paul Kellam, Ian R. Humphreys
B cells contribute to multiple aspects of autoimmune disorders and may play a role in triggering disease. Thus, targeting B cells may be a promising strategy for treating autoimmune disorders. Better understanding of the B cell subsets that are responsible for the development of autoimmunity will be critical for developing efficient therapies. Here we have reported that B cells expressing the transcription factor T-bet promote the rapid appearance of autoantibodies and germinal centers in spontaneous murine models of systemic lupus erythematosus (SLE). Conditional deletion of T-bet from B cells impaired the formation of germinal centers and mitigated the development of kidney damage and rapid mortality in SLE mice. B cell–specific deletion of T-bet was also associated with lower activation of both B cells and T cells. Taken together, our results suggest that targeting T-bet–expressing B cells may be a potential target for therapy for autoimmune diseases.
Kira Rubtsova, Anatoly V. Rubtsov, Joshua M. Thurman, Johanna M. Mennona, John W. Kappler, Philippa Marrack
Autoimmune responses to meiotic germ cell antigens (MGCA) that are expressed on sperm and testis occur in human infertility and after vasectomy. Many MGCA are also expressed as cancer/testis antigens (CTA) in human cancers, but the tolerance status of MGCA has not been investigated. MGCA are considered to be uniformly immunogenic and nontolerogenic, and the prevailing view posits that MGCA are sequestered behind the Sertoli cell barrier in seminiferous tubules. Here, we have shown that only some murine MGCA are sequestered. Nonsequestered MCGA (NS-MGCA) egressed from normal tubules, as evidenced by their ability to interact with systemically injected antibodies and form localized immune complexes outside the Sertoli cell barrier. NS-MGCA derived from cell fragments that were discarded by spermatids during spermiation. They egressed as cargo in residual bodies and maintained Treg-dependent physiological tolerance. In contrast, sequestered MGCA (S-MGCA) were undetectable in residual bodies and were nontolerogenic. Unlike postvasectomy autoantibodies, which have been shown to mainly target S-MGCA, autoantibodies produced by normal mice with transient Treg depletion that developed autoimmune orchitis exclusively targeted NS-MGCA. We conclude that spermiation, a physiological checkpoint in spermatogenesis, determines the egress and tolerogenicity of MGCA. Our findings will affect target antigen selection in testis and sperm autoimmunity and the immune responses to CTA in male cancer patients.
Kenneth S.K. Tung, Jessica Harakal, Hui Qiao, Claudia Rival, Jonathan C.H. Li, Alberta G.A. Paul, Karen Wheeler, Patcharin Pramoonjago, Constance M. Grafer, Wei Sun, Robert D. Sampson, Elissa W.P. Wong, Prabhakara P. Reddi, Umesh S. Deshmukh, Daniel M. Hardy, Huanghui Tang, C. Yan Cheng, Erwin Goldberg
Defective apoptotic death of activated macrophages has been implicated in the pathogenesis of rheumatoid arthritis (RA). However, the molecular signatures defining apoptotic resistance of RA macrophages are not fully understood. Here, global transcriptome profiling of RA macrophages revealed that the osmoprotective transcription factor nuclear factor of activated T cells 5 (NFAT5) critically regulates diverse pathologic processes in synovial macrophages including the cell cycle, apoptosis, and proliferation. Transcriptomic analysis of NFAT5-deficient macrophages revealed the molecular networks defining cell survival and proliferation. Proinflammatory M1-polarizing stimuli and hypoxic conditions were responsible for enhanced NFAT5 expression in RA macrophages. An in vitro functional study demonstrated that NFAT5-deficient macrophages were more susceptible to apoptotic death. Specifically, CCL2 secretion in an NFAT5-dependent fashion bestowed apoptotic resistance to RA macrophages in vitro. Injection of recombinant CCL2 into one of the affected joints of
Susanna Choi, Sungyong You, Donghyun Kim, Soo Youn Choi, H. Moo Kwon, Hyun-Sook Kim, Daehee Hwang, Yune-Jung Park, Chul-Soo Cho, Wan-Uk Kim