Curing HIV infection will require the elimination of a reservoir of infected CD4+ T-cells that persists despite HIV-specific cytotoxic T-cell (CTL) responses. While viral latency is a critical factor in this persistence, recent evidence also suggests a role for intrinsic resistance of reservoir-harboring cells to CTL killing. This resistance may have contributed to negative outcomes of clinical trials, where pharmacologic latency reversal has thus far failed to drive reductions in HIV reservoirs. Through transcriptional profiling, we herein identified over-expression of the pro-survival factor BCL-2 as a distinguishing feature of CD4+ T-cells that survived CTL killing. We show that the inducible HIV reservoir was disproportionately present in BCL-2hi subsets, in ex vivo CD4+ T-cells. Treatment with the BCL-2 antagonist ‘ABT-199’ alone was not sufficient to drive reductions in ex vivo viral reservoirs, when tested either alone or with a latency reversing agent (LRA). However, the triple combination of strong LRAs, HIV-specific T-cells, and a BCL-2 antagonist uniquely enabled the depletion of ex vivo viral reservoirs. Our results provide rationale for novel therapeutic approaches targeting HIV cure and, more generally, suggest consideration of BCL-2 antagonism as a means of enhancing CTL immunotherapy in other settings, such as cancer.
Yanqin Ren, Szu-Han Huang, Shabnum Patel, Winiffer D. Conce Alberto, Dean Magat, Dughan J. Ahimovic, Amanda B. Macedo, Ryan Durga, Dora Chan, Elizabeth Zale, Talia M. Mota, Ronald Truong, Thomas Rohwetter, Chase D. McCann, Colin M. Kovacs, Erika Benko, Avery Wimpelberg, Christopher M. Cannon, W. David Hardy, Alberto Bosque, Catherine M. Bollard, R. Brad Jones
Whether mutations in cancer driver genes directly affect cancer immune phenotype and T cell immunity remains a standing question. ARID1A is a core member of the polymorphic BAF chromatin remodeling complex. ARID1A mutations occur in human cancers and drive cancer development. Here, we studied the molecular, cellular, and clinical impact of ARID1A aberrations on cancer immunity. We demonstrated that ARID1A aberrations resulted in limited chromatin accessibility to interferon (IFN) responsive genes, caused impaired IFN-gene expression, anemic T cell tumor infiltration, poor tumor immunity, and shortened host survival in many human cancer histologies as well as in murine cancer models. Impaired IFN signaling was associated with poor immunotherapy response. Mechanistically, ARID1A interacted with EZH2 via its carboxyl terminal and antagonized EZH2-mediated IFN responsiveness. Thus, the interaction between ARID1A and EZH2 defines cancer IFN-responsiveness and immune evasion. Our work indicates that cancer epigenetic driver mutations can shape cancer immune phenotype and immunotherapy.
Jing Li, Weichao Wang, Yajia Zhang, Marcin Cieślik, Jipeng Guo, Mengyao Tan, Michael D. Green, Weimin Wang, Heng Lin, Wei Li, Shuang Wei, Jiajia Zhou, Gaopeng Li, Xiaojun Jing, Linda Vatan, Lili Zhao, Benjamin Bitler, Rugang Zhang, Kathleen R. Cho, Yali Dou, Ilona Kryczek, Timothy A. Chan, David Huntsman, Arul M. Chinnaiyan, Weiping Zou
Lymph node stromal cells (LNSC) regulate immunity through constructing lymphocyte niches. LNSC produced Laminin α5 (Lama5) regulates CD4 T cells but the underlying mechanisms of its functions are poorly understood. Here we showed depleting Lama5 in LNSC resulted in decreased Lama5 protein in the LN cortical ridge (CR) and around high endothelial venules (HEV). Lama5 depletion affected LN structure with increased HEV, upregulated chemokines and cell adhesion molecules, and led to greater numbers of Treg in T cell zone. Mouse and human T cell transendothelial migration and T cell entry to LN were suppressed by Lama5 through the receptors a6 integrin and α-dystroglycan. During immune responses and allograft transplantation, depleting Lama5 promoted antigen specific CD4 T cell entry to the CR through HEV, suppressed T cell activation and altered T cell differentiation to suppressive regulatory phenotypes. Enhanced allograft acceptance resulted from depleting Lama5 or blockade of T cell Lama5 receptors. Lama5 and Lama4:Lama5 ratios in allografts were associated with the rejection severity. Overall, our results demonstrated that stromal Lama5 regulated immune responses through altering LN structures and T cell behaviors. The study delineated a stromal Lama5-T cell receptors axis that can be targeted for immune tolerance modulation.
Lushen Li, Marina W. Shirkey, Tianshu Zhang, Yanbao Xiong, Wenji Piao, Vikas Saxena, Christina Paluskievicz, Young S. Lee, Nicholas Toney, Benjamin M. Cerel, Qinshan Li, Thomas Simon, Kyle D. Smith, Keli L. Hippen, Bruce R. Blazar, Reza Abdi, Jonathan S. Bromberg
Plasmacytoid dendritic cells (pDCs) are robust producers of interferon α (IFNα) and one of the first immune cells to respond to simian immunodeficiency virus infection. To elucidate responses to early HIV-1 replication, we studied blood pDCs in 29 HIV-infected participants who initiated antiretroviral therapy during acute infection and underwent analytic treatment interruption (ATI). An increased frequency of partially activated pDCs was observed in the blood prior to detection of HIV RNA. Concurrent with peak pDC frequency, there was a transient decline in the ability of pDCs to produce IFNα in vitro, which correlated with decreased interferon regulatory factory 7 (IRF7) and NF-kB phosphorylation. Levels of phosphorylated IRF7 and NF-kB inversely correlated with plasma IFNα2 levels, implying that pDCs were refractory to in vitro stimulation after IFNα production in vivo. After ATI, decreased expression of IFN genes in pDCs inversely correlated with time to viral detection, suggesting that pDC IFN loss is part of an effective early immune response. These data, from a limited cohort, provide a critical first step in understanding the earliest immune response to HIV-1 and suggest that changes in blood pDC frequency and function can be used as an indicator of viral replication before detectable plasma viremia.
Julie L. Mitchell, Hiroshi Takata, Roshell Muir, Donn J. Colby, Eugene Kroon, Trevor A. Crowell, Carlo Sacdalan, Suteeraporn Pinyakorn, Suwanna Pattamaswin, Khunthalee Benjapornpong, Rapee Trichavaroj, Randall L. Tressler, Lawrence Fox, Victoria R. Polonis, Diane L. Bolton, Frank Maldarelli, Sharon R. Lewin, Elias K. Haddad, Praphan Phanuphak, Merlin L. Robb, Nelson L. Michael, Mark de Souza, Nittaya Phanuphak, Jintanat Ananworanich, Lydie Trautmann
An in-depth understanding of immune escape mechanisms in cancer are likely to lead to innovative advances in immunotherapeutic strategies. However, much remains unknown regarding these mechanisms and how they impact immunotherapy resistance. Using several pre-clinical tumor models as well as clinical specimens, we report a newly identified mechanism whereby CD8+ T cell activation in response to PD-1 blockade induced a PD-L1-NLRP3 inflammasome signaling cascade that ultimately led to the recruitment of granulocytic myeloid-derived suppressor cells (PMN-MDSCs) into tumor tissues, thereby dampening the resulting anti-tumor immune response. The genetic and pharmacologic inhibition of NLRP3 suppressed PMN-MDSC tumor infiltration and significantly augmented the efficacy of anti-PD-1 antibody immunotherapy. This pathway therefore represents a tumor-intrinsic adaptive resistance mechanism to anti-PD-1 checkpoint inhibitor immunotherapy and is a promising target for future translational research.
Balamayooran Theivanthiran, Kathy S. Evans, Nicholas C. DeVito, Michael P. Plebanek, Michael Sturdivant, Lucas P. Wachsmuth, April K.S. Salama, Yubin Kang, David Hsu, Justin M. Balko, Douglas B. Johnson, Mark Starr, Andrew B. Nixon, Alisha Holtzhausen, Brent A. Hanks
Background: Neurofibroma/schwannoma hybrid nerve sheath tumors (N/S HNSTs) are neoplasms associated with larger nerves that occur sporadically and in the context of schwannomatosis or neurofibromatosis type 2 or 1. Clinical management of N/S HNST is challenging, especially for large tumors, and established systemic treatments are lacking. Methods: We used next-generation sequencing and array-based DNA methylation profiling to determine the clinically actionable genomic and epigenomic landscapes of N/S HNST. Results: Whole-exome sequencing within a precision oncology program identified an activating mutation (p.Asp769Tyr) in the catalytic domain of the ERBB2 receptor tyrosine kinase in a patient with schwannomatosis-associated N/S HNST, and targeted treatment with the small-molecule ERBB inhibitor lapatinib led to prolonged clinical benefit and a lasting radiographic and metabolic response. Analysis of a multicenter validation cohort revealed recurrent ERBB2 mutations (p.Leu755Ser, p.Asp769Tyr, p.Val777Leu) in N/S HNSTs occurring in patients who met diagnostic criteria for sporadic schwannomatosis (3 of 7 patients), but not in N/S HNSTs arising in the context of neurofibromatosis (6 patients) or outside a tumor syndrome (1 patient), and showed that ERBB2-mutant N/S HNSTs cluster in a distinct subgroup of peripheral nerve sheath tumors based on genome-wide DNA methylation patterns. Conclusion: These findings uncover a key biological feature of N/S HNST that may have important diagnostic and therapeutic implications. Funding: This work was supported by grant H021 from DKFZ-HIPO. MWR and PNH have received fellowships from UCT Frankfurt, and MWR has received funding from the Frankfurt Research Funding Clinician Scientist Program.
Michael W. Ronellenfitsch, Patrick N. Harter, Martina Kirchner, Christoph Heining, Barbara Hutter, Laura Gieldon, Jens Schittenhelm, Martin U. Schuhmann, Marcos Tatagiba, Gerhard Marquardt, Marlies Wagner, Volker Endris, Christian H. Brandts, Victor-Felix Mautner, Evelin Schröck, Wilko Weichert, Benedikt Brors, Andreas von Deimling, Michel Mittelbronn, Joachim P. Steinbach, David E. Reuss, Hanno Glimm, Albrecht Stenzinger, Stefan Fröhling
Hepatocellular carcinoma (HCC) is clearly age-related and represents one of the deadliest cancer types worldwide. Due to globally increasing risk factors including metabolic disorders, the incidence rates of HCC are still rising. However, the molecular hallmarks of HCC remain poorly understood. Neuropeptide Y (NPY) and NPY-receptors represent a highly conserved, stress-activated system which is involved in diverse cancer-related hallmarks including aging and metabolic alterations, but its impact on liver cancer had been unclear. Here, we observed increased NPY5-receptor (Y5R) expression in HCC which correlated with tumor growth and survival. Furthermore, we found that its ligand NPY was secreted by peri-tumorous hepatocytes. Hepatocyte-derived NPY promoted HCC progression by Y5R-activation. Transforming growth factor beta 1 (TGFβ1) was identified as a regulator of NPY in hepatocytes and induced Y5R in invasive cancer cells. Moreover, NPY-conversion by dipeptidylpeptidase 4 (DPP4) augmented Y5R-activation and function in liver cancer. The TGFβ-NPY-Y5R-axis and DPP4 represent attractive therapeutic targets for controlling liver cancer progression.
Peter Dietrich, Laura Wormser, Valerie Fritz, Tatjana Seitz, Monica De Maria, Alexandra Schambony, Andreas E. Kremer, Claudia Günther, Timo Itzel, Wolfgang E. Thasler, Andreas Teufel, Jonel Trebicka, Arndt Hartmann, Markus F. Neurath, Stephan von Hörsten, Anja Bosserhoff, Claus Hellerbrand
Treating neuropathic pain is challenging and novel non-opioid based medicines are needed. Using unbiased receptomics, transcriptomic analyses, immunofluorescence and in situ hybridization, we found the expression of the orphan GPCR (oGPCR) Gpr160 and GPR160 increased in the rodent dorsal horn of the spinal cord (DH-SC) following traumatic nerve injury. Genetic and immunopharmacological approaches demonstrated that GPR160 inhibition in the spinal cord prevented and reversed neuropathic pain in male and female rodents without altering normal pain response. GPR160 inhibition in the spinal cord attenuated sensory processing in the thalamus, a key relay in the sensory discriminative pathways of pain. We also identified cocaine- and amphetamine-regulated transcript peptide (CARTp) as a GPR160 ligand. Inhibiting endogenous CARTp signaling in spinal cord attenuated neuropathic pain, whereas exogenous intrathecal (i.th.) CARTp evoked painful hypersensitivity through GPR160-dependent ERK and cAMP response element-binding protein (CREB). Our findings de-orphanize GPR160, identify it as a determinant of neuropathic pain and potential therapeutic target, and provide insights to its signaling pathways. CARTp is involved in many diseases including depression, reward and addiction, de-orphanization of GPR160 is a major step forward understanding the role of CARTp signaling in health and disease.
Gina LC Yosten, Caron M. Harada, Christopher J. Haddock, Luigino Antonio Giancotti, Grant R. Kolar, Ryan Patel, Chun Guo, Zhoumou Chen, Jinsong Zhang, Timothy M. Doyle, Anthony H. Dickenson, Willis K. Samson, Daniela Salvemini
Lamin A is a component of the inner nuclear membrane that, together with epigenetic factors, organizes the genome in higher order structures required for transcriptional control. Mutations in the Lamin A/C gene cause several diseases, belonging to the class of laminopathies, including muscular dystrophies. Nevertheless, molecular mechanisms involved in the pathogenesis of Lamin A-dependent dystrophies are still largely unknown. Polycomb group of proteins (PcG) are epigenetic repressors and Lamin A interactors, primarily involved in the maintenance of cell identity. Using a murine model of Emery-Dreifuss Muscular Dystrophy (EDMD), we showed here that Lamin A loss deregulated PcG positioning in muscle satellite stem cells leading to de-repression of non-muscle specific genes and p16INK4a, a senescence driver encoded in the Cdkn2a locus. This aberrant transcriptional programme caused impairment in self-renewal, loss of cell identity and premature exhaustion of quiescent satellite cell pool. Genetic ablation of Cdkn2a locus restored muscle stem cell properties in Lamin A/C null dystrophic mice. Our findings established a direct link between Lamin A and PcG epigenetic silencing and indicated that Lamin A-dependent muscular dystrophy can be ascribed to intrinsic epigenetic dysfunctions of muscle stem cells.
Andrea Bianchi, Chiara Mozzetta, Gloria Pegoli, Federica Lucini, Sara Valsoni, Valentina Rosti, Cristiano Petrini, Alice Cortesi, Francesco Gregoretti, Laura Antonelli, Gennaro Oliva, Marco De Bardi, Roberto Rizzi, Beatrice Bodega, Diego Pasini, Francesco Ferrari, Claudia Bearzi, Chiara Lanzuolo
Elevated pressure in the pancreatic gland is the central cause of pancreatitis following abdominal trauma, surgery, endoscopic retrograde cholangiopancreatography (ERCP), and gallstones. In the pancreas excessive intracellular calcium causes mitochondrial dysfunction, premature zymogen activation, and necrosis ultimately leading to pancreatitis. Although stimulation of the mechanically activated, calcium-permeable ion channel, Piezo1, in the pancreatic acinar cell is the initial step in pressure-induced pancreatitis, activation of Piezo1 produces only transient elevation in intracellular calcium that is insufficient to cause pancreatitis. Therefore, how pressure produces a prolonged calcium elevation necessary to induce pancreatitis is unknown. We demonstrate that Piezo1 activation in pancreatic acinar cells caused a prolonged elevation in intracellular calcium levels, mitochondrial depolarization, intracellular trypsin activation, and cell death. Notably, these effects were dependent on the degree and duration of force applied to the cell. Low or transient force were insufficient to activate these pathological changes whereas higher and prolonged application of force triggered sustained elevation in intracellular calcium leading to enzyme activation and cell death. All of these pathological events were rescued in acinar cells treated with a Piezo1 antagonist and in acinar cells from mice with genetic deletion of Piezo1. We discovered that Piezo1 stimulation triggered TRPV4 channel opening which was responsible for the sustained elevation in intracellular calcium that caused intracellular organelle dysfunction. Moreover, TRPV4 gene knockout mice were protected from Piezo1 agonist- and pressure-induced pancreatitis. These studies unveil a calcium signaling pathway in which Piezo1-induced TRPV4 channel opening causes pancreatitis.
Sandip M. Swain, Joelle M.J. Romac, Rafiq A. Shahid, Stephen J. Pandol, Wolfgang Liedtke, Steven R. Vigna, Rodger A. Liddle
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