Immunology
Abstract
PD-L1 is a promising therapeutic target in aggressive cancers. However, immune landscapes and cancer hallmarks of human PD-L1+ tumors, as well as their roles in determining therapeutic efficacies are unknown. Here we identified, in detailed studies of gene data regarding 9769 patients of 32 types of human cancers, that PD-L1 could not exclusively represent IFN-γ signature and potentially signified pro-inflammatory myeloid responses in a tumor. PD-L1 heterogeneity endowed by local immune landscapes controlled cancer hallmarks and clinical outcomes of patients. Mechanically, NF-κB signal elicited by macrophage inflammatory responses generated PD-L1+ cancer cells exhibiting capabilities to aggressively survive, support angiogenesis, and metastasize, whereas STAT1 signal triggered by activated T cells induced PD-L1+ cancer cells susceptive to apoptosis. Importantly, PD-L1+ cancer cells generated by macrophages established great resistance to conventional chemotherapy, cytotoxicity of tumor-specific effector T cells, and therapy of immune checkpoint blockade. Therapeutic strategy combining immune checkpoint blockade with macrophage depletion or NF-κB inhibition in vivo effectively and successfully elicited caner regression. Our results provide insight into the functional features of PD-L1+ tumors and suggest that strategies to influence functional activities of inflammatory cells may benefit immune checkpoint blockade therapy.
Authors
Yuan Wei, Qiyi Zhao, Zhiliang Gao, Xiang-Ming Lao, Wei-Ming Lin, Dong-Ping Chen, Ming Mu, Chun-Xiang Huang, Zheng-Yu Liu, Bo Li, Limin Zheng, Dong-Ming Kuang
Abstract
Prevalence of obesity among infants and children below 5 years of age is rising dramatically, and early childhood obesity is a forerunner of obesity and obesity-associated diseases in adulthood. Childhood obesity is hence one of the most serious public health challenges today. Here, we have identified a mother-to-child lipid signaling that protects from obesity. We have found that breast milk–specific lipid species, so-called alkylglycerol-type (AKG-type) ether lipids, which are absent from infant formula and adult-type diets, maintain beige adipose tissue (BeAT) in the infant and impede the transformation of BeAT into lipid-storing white adipose tissue (WAT). Breast milk AKGs are metabolized by adipose tissue macrophages (ATMs) to platelet-activating factor (PAF), which ultimately activates IL-6/STAT3 signaling in adipocytes and triggers BeAT development in the infant. Accordingly, lack of AKG intake in infancy leads to a premature loss of BeAT and increases fat accumulation. AKG signaling is specific for infants and is inactivated in adulthood. However, in obese adipose tissue, ATMs regain their ability to metabolize AKGs, which reduces obesity. In summary, AKGs are specific lipid signals of breast milk that are essential for healthy adipose tissue development.
Authors
Haidong Yu, Sedat Dilbaz, Jonas Coßmann, Anh Cuong Hoang, Victoria Diedrich, Annika Herwig, Akiko Harauma, Yukino Hoshi, Toru Moriguchi, Kathrin Landgraf, Antje Körner, Christina Lucas, Susanne Brodesser, Lajos Balogh, Julianna Thuróczy, Gopal Karemore, Michael Scott Kuefner, Edwards A. Park, Christine Rapp, Jeffrey Bryant Travers, Tamás Röszer
Abstract
Oxidative stress is elevated in the recipients of allogeneic hematopoietic transplantation (allo-HCT) and likely contributes to the development of graft-versus-host disease (GVHD). GVHD is characterized by activation, expansion, cytokine production and migration of alloreactive donor T cells, and remains a major cause of morbidity and mortality after allo-HCT. Hence, strategies to limit oxidative stress in GVHD are highly desirable. Thioredoxin1 (Trx1) counteracts oxidative stress by scavenging reactive oxygen species (ROS) and regulating other enzymes that metabolize H2O2. The present study sought to elucidate the role of Trx1 in the pathophysiology of GVHD. Using murine and xenograft models of allogeneic bone marrow transplantation (allo-BMT) and genetic (human Trx1-transgenic, Trx1-Tg) as well as pharmacologic (human recombinant Trx1, RTrx1) strategies; we found that Trx1-Tg donor T cells or administration of the recipients with RTrx1 significantly reduced GVHD severity. Mechanistically, we observed RTrx1 reduced ROS accumulation and cytokine production of mouse and human T cells in response to alloantigen stimulation in vitro. In allo-BMT settings, we found that Trx1-Tg or RTrx1 decreased downstream signaling molecules including NFκB activation and T-bet expression, and reduced proliferation, IFN-γ production and ROS accumulation in donor T cells within GVHD target organs. More importantly, administration of RTrx1 did not impair the graft-versus-leukemia (GVL) effect. Taken together, the current work provides a strong rationale and demonstrates feasibility to target the ROS pathway, which can be readily translated into clinic.
Authors
M. Hanief Sofi, Yongxia Wu, Steven D. Schutt, Min Dai, Anusara Daenthanasanmak, Jessica Heinrichs Voss, Hung Nguyen, David Bastian, Supinya Iamsawat, Shanmugam Panneer Selvam, Chen Liu, Nilanjana Maulik, Besim Ogretmen, Junfei Jin, Shikhar Mehrotra, Xue-Zhong Yu
Abstract
Influenza A virus (IAV)-specific T cell responses are important correlates of protection during primary and subsequent infections. Generation and maintenance of robust IAV-specific T cell responses relies on T cell interactions with dendritic cells (DCs). In this study, we explore the role of nucleotide-binding domain leucine-rich repeat containing receptor family member NLRC4 in modulating the DC phenotype during IAV infection. Nlrc4-/- mice had worsened survival and increased viral titers during infection, normal innate immune cell recruitment and IAV-specific CD8 T cell responses, but severely blunted IAV-specific CD4 T cell responses compared to wild-type mice. The defect in the pulmonary IAV-specific CD4 T cell response was not a result of defective priming or migration of these cells in Nlrc4-/- mice but was instead due to an increase in FasL+ DCs, resulting in IAV-specific CD4 T cell death. Together, our data support a novel role for NLRC4 in regulating the phenotype of lung DCs during a respiratory viral infection, and thereby influencing the magnitude of protective T cell responses.
Authors
Emma E. Hornick, Jargalsaikhan Dagvadorj, Zeb R. Zacharias, Ann M. Miller, Ryan A. Langlois, Peter Chen, Kevin L. Legge, Gail A. Bishop, Fayyaz S. Sutterwala, Suzanne L. Cassel
Abstract
T cell therapy is a promising means to treat chronic HBV infection and HBV-associated hepatocellular carcinoma. T cells engineered to express an HBV-specific T cell receptor (TCR) may achieve cure of HBV infection upon adoptive transfer. We investigated the therapeutic potential and safety of T cells stably expressing high affinity HBV envelope- or core-specific TCRs recognizing European and Asian HLA-A2 subtypes. Both CD8+ and CD4+ T cells from healthy donors and from chronic hepatitis B patients became polyfunctional effector cells when grafted with HBV-specific TCRs and eliminated HBV from infected HepG2-NTCP cell cultures. A single transfer of TCR-grafted T cells into HBV-infected, humanized mice controlled HBV infection and virological markers declined 4-5 log or below detection limit. When — as in a typical clinical setting — only a minority of hepatocytes were infected, engineered T cells specifically cleared infected hepatocytes without damaging non-infected cells. Cell death was compensated by hepatocyte proliferation and alanine amino transferase levels peaking at day 5 to 7 normalized again thereafter. Co-treatment with the entry inhibitor Myrcludex B ensured long-term control of HBV infection. Thus, T cells stably transduced with highly functional TCRs have the potential to mediate clearance of HBV-infected cells causing limited liver injury.
Authors
Karin Wisskirchen, Janine Kah, Antje Malo, Theresa Asen, Tassilo Volz, Lena Allweiss, Jochen M. Wettengel, Marc Lütgehetmann, Stephan Urban, Tanja Bauer, Maura Dandri, Ulrike Protzer
Abstract
Diabetic individuals are at considerable risk for invasive infection by Staphylococcus aureus, however, the mechanisms underlying this enhanced susceptibility to infection are unclear. We observed increased mortality following i.v. S. aureus infection in diabetic mice compared with nondiabetic controls, correlating with increased numbers of low-density neutrophils (LDNs) and neutrophil extracellular traps (NETs). LDNs have been implicated in the inflammatory pathology of diseases such as lupus, given their release of large amounts of NETs. Our goal was to describe what drives LDN increases during S. aureus infection in the diabetic host and mechanisms that promote increased NET production by LDNs. LDN development is dependent on TGF-β, which we found to be more activated in the diabetic host. Neutralization of TGF-β, or the TGF-β–activating integrin αvβ8, reduced LDN numbers and improved survival during S. aureus infection. Targeting S. aureus directly with MEDI4893*, an α toxin–neutralizing monoclonal antibody, blocked TGF-β activation, reduced LDNs and NETs, and significantly improved survival. A comparison of gene and protein expression in high-density neutrophils and LDNs identified increased GPCRs and elevated phosphatase and tensin homolog (PTEN) in the LDN subset. Inhibition of PTEN improved the survival of infected diabetic mice. Our data identify a population of neutrophils in infected diabetic mice that correlated with decreased survival and increased NET production and describe 3 therapeutic targets, a bacterial target and 2 host proteins, that prevented NET production and improved survival.
Authors
Taylor S. Cohen, Virginia Takahashi, Jessica Bonnell, Andrey Tovchigrechko, Raghothama Chaerkady, Wen Yu, Omari Jones-Nelson, Young Lee, Rajiv Raja, Sonja Hess, C. Kendall Stover, John J. Worthington, Mark A. Travis, Bret R. Sellman
Abstract
DCs undergo metabolic reprogramming from a predominantly oxidative phosphorylation (OXPHOS) to glycolysis to mount an immunogenic response. The mechanism underpinning the metabolic reprogramming remains elusive. We demonstrate that miRNA-142 (miR-142) is pivotal for this shift in metabolism, which regulates the tolerogenic and immunogenic responses of DCs. In the absence of miR-142, DCs fail to switch from OXPHOS and show reduced production of proinflammatory cytokines and the ability to activate T cells in vitro and in in vivo models of sepsis and alloimmunity. Mechanistic studies demonstrate that miR-142 regulates fatty acid (FA) oxidation, which causes the failure to switch to glycolysis. Loss- and gain-of-function experiments identified carnitine palmitoyltransferase -1a (CPT1a), a key regulator of the FA pathway, as a direct target of miR-142 that is pivotal for the metabolic switch. Thus, our findings show that miR-142 is central to the metabolic reprogramming that specifically favors glycolysis and immunogenic response by DCs.
Authors
Yaping Sun, Katherine Oravecz-Wilson, Sydney Bridges, Richard McEachin, Julia Wu, Stephanie H. Kim, Austin Taylor, Cynthia Zajac, Hideaki Fujiwara, Daniel Christopher Peltier, Thomas Saunders, Pavan Reddy
Abstract
T cell heterogeneity is highly relevant to allergic disorders. We resolved the heterogeneity of human tissue CD3+ T cells during allergic inflammation, focusing on a tissue-specific allergic disease, eosinophilic esophagitis (EoE). We investigated 1088 single T cells derived from patients with a spectrum of disease activity. Eight disparate tissue T cell subtypes (designated T1–T8) were identified, with T7 and T8 enriched in the diseased tissue. The phenotypes of T7 and T8 resemble putative Treg (FOXP3+) and effector Th2-like (GATA3+) cells, respectively. Prodigious levels of IL-5 and IL-13 were confined to HPGDS+ CRTH2+IL-17RB+FFAR3+CD4+ T8 effector Th2 cells. EoE severity closely paralleled a lipid/fatty acid–induced activation node highlighted by the expression of the short-chain fatty acid receptor FFAR3. Ligands for FFAR3 induced Th2 cytokine production from human and murine T cells, including in an in vivo allergy model. Therefore, we elucidated the defining characteristics of tissue-residing CD3+ T cells in EoE, a specific enrichment of CD4+ Treg and effector Th2 cells, confinement of type 2 cytokine production to the CD4+ effector population, a highly likely role for FFAR3 in amplifying local Th2 responses in EoE, and a resource to further dissect tissue lymphocytes and allergic responses.
Authors
Ting Wen, Bruce J. Aronow, Yrina Rochman, Mark Rochman, Kiran KC, Phil J. Dexheimer, Philip Putnam, Vincent Mukkada, Heather Foote, Kira Rehn, Sam Darko, Daniel Douek, Marc E. Rothenberg
IL-7 receptor influences anti-TNF responsiveness and T cell gut homing in inflammatory bowel disease
Abstract
It remains unknown what causes inflammatory bowel disease (IBD), including signaling networks perpetuating chronic gastrointestinal inflammation in Crohn’s disease (CD) and ulcerative colitis (UC), in humans. According to an analysis of up to 500 patients with IBD and 100 controls, we report that key transcripts of the IL-7 receptor (IL-7R) pathway are accumulated in inflamed colon tissues of severe CD and UC patients not responding to either immunosuppressive/corticosteroid, anti-TNF, or anti-α4β7 therapies. High expression of both IL7R and IL-7R signaling signature in the colon before treatment is strongly associated with nonresponsiveness to anti-TNF therapy. While in mice IL-7 is known to play a role in systemic inflammation, we found that in humans IL-7 also controlled α4β7 integrin expression and imprinted gut-homing specificity on T cells. IL-7R blockade reduced human T cell homing to the gut and colonic inflammation in vivo in humanized mouse models, and altered effector T cells in colon explants from UC patients grown ex vivo. Our findings show that failure of current treatments for CD and UC is strongly associated with an overexpressed IL-7R signaling pathway and point to IL-7R as a relevant therapeutic target and potential biomarker to fill an unmet need in clinical IBD detection and treatment.
Authors
Lyssia Belarif, Richard Danger, Laetitia Kermarrec, Véronique Nerrière-Daguin, Sabrina Pengam, Tony Durand, Caroline Mary, Elise Kerdreux, Vanessa Gauttier, Aneta Kucik, Virginie Thepenier, Jerome C. Martin, Christie Chang, Adeeb Rahman, Nina Salabert-Le Guen, Cécile Braudeau, Ahmed Abidi, Grégoire David, Florent Malard, Celine Takoudju, Bernard Martinet, Nathalie Gérard, Isabelle Neveu, Michel Neunlist, Emmanuel Coron, Thomas T. MacDonald, Pierre Desreumaux, Hoa-Le Mai, Stephanie Le Bas-Bernardet, Jean-François Mosnier, Miriam Merad, Régis Josien, Sophie Brouard, Jean-Paul Soulillou, Gilles Blancho, Arnaud Bourreille, Philippe Naveilhan, Bernard Vanhove, Nicolas Poirier
Abstract
IL-26 is an antimicrobial protein secreted by Th17 cells that has the ability to directly kill extracellular bacteria. To ascertain whether IL-26 contributes to host defense against intracellular bacteria, we studied leprosy, caused by the obligate intracellular pathogen Mycobacterium leprae, as a model. Analysis of leprosy skin lesions by gene expression profiling and immunohistology revealed that IL-26 was more strongly expressed in lesions from the self-limited tuberculoid compared with expression in progressive lepromatous patients. IL-26 directly bound to M. leprae in axenic culture and reduced bacteria viability. Furthermore, IL-26, when added to human monocyte–derived macrophages infected with M. leprae, entered the infected cell, colocalized with the bacterium, and reduced bacteria viability. In addition, IL-26 induced autophagy via the cytoplasmic DNA receptor stimulator of IFN genes (STING), as well as fusion of phagosomes containing bacilli with lysosomal compartments. Altogether, our data suggest that the Th17 cytokine IL-26 contributes to host defense against intracellular bacteria.
Authors
Angeline Tilly Dang, Rosane M.B. Teles, David I. Weiss, Kislay Parvatiyar, Euzenir N. Sarno, Maria T. Ochoa, Genhong Cheng, Michel Gilliet, Barry R. Bloom, Robert L. Modlin
Copyright © 2019 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)