Cancer cells can inhibit effector T cells (Teff) through both immunomodulatory receptors and the impact of cancer metabolism on the tumor microenvironment. Indeed, Teff require high rates of glucose metabolism, and consumption of essential nutrients or generation of waste products by tumor cells may impede essential T cell metabolic pathways. Clear cell renal cell carcinoma (ccRCC) is characterized by loss of the tumor suppressor von Hippel-Lindau (VHL) and altered cancer cell metabolism. Here, we assessed how ccRCC influences the metabolism and activation of primary patient ccRCC tumor infiltrating lymphocytes (TIL). CD8 TIL were abundant in ccRCC, but they were phenotypically distinct and both functionally and metabolically impaired. ccRCC CD8 TIL were unable to efficiently uptake glucose or perform glycolysis and had small, fragmented mitochondria that were hyperpolarized and generated large amounts of ROS. Elevated ROS was associated with downregulated mitochondrial SOD2. CD8 T cells with hyperpolarized mitochondria were also visible in the blood of ccRCC patients. Importantly, provision of pyruvate to bypass glycolytic defects or scavengers to neutralize mitochondrial ROS could partially restore TIL activation. Thus, strategies to improve metabolic function of ccRCC CD8 TIL may promote the immune response to ccRCC.
Peter J. Siska, Kathryn E. Beckermann, Frank M. Mason, Gabriela Andrejeva, Allison R. Greenplate, Adam B. Sendor, Yun-Chen J. Chiang, Armando L. Corona, Lelisa F. Gemta, Benjamin G. Vincent, Richard C. Wang, Bumki Kim, Jiyong Hong, Chiu-lan Chen, Timothy N. Bullock, Jonathan M. Irish, W. Kimryn Rathmell, Jeffrey C. Rathmell
Conventional histologic diagnosis of rejection in kidney transplants has limited repeatability due to its inherent requirement for subjective assessment of lesions, in a rule-based system that does not acknowledge diagnostic uncertainty. Molecular phenotyping affords opportunities for increased precision and improved disease classification to address the limitations of conventional histologic diagnostic systems and quantify levels of uncertainty. Microarray data from 1,208 kidney transplant biopsies were collected prospectively from 13 centers. Cross-validated classifier scores predicting the presence of antibody-mediated rejection (ABMR), T cell–mediated rejection (TCMR), and 5 related histologic lesions were generated using supervised machine learning methods. These scores were used as input for archetypal analysis, an unsupervised method similar to cluster analysis, to examine the distribution of molecular phenotypes related to rejection. Six archetypes were generated: no rejection, TCMR, 3 associated with ABMR (early-stage, fully developed, and late-stage), and mixed rejection (TCMR plus early-stage ABMR). Each biopsy was assigned 6 scores, one for each archetype, representing a probabilistic assessment of that biopsy based on its rejection-related molecular properties. Viewed as clusters, the archetypes were similar to existing histologic Banff categories, but there was 32% disagreement, much of it probably reflecting the “noise” in the current histologic assessment system. Graft survival was lowest for fully developed and late-stage ABMR, and it was better predicted by molecular archetype scores than histologic diagnoses. The results provide a system for precision molecular assessment of biopsies and a new standard for recalibrating conventional diagnostic systems.
Jeff Reeve, Georg A. Böhmig, Farsad Eskandary, Gunilla Einecke, Carmen Lefaucheur, Alexandre Loupy, Philip F. Halloran, the MMDx-Kidney study group
A fundamental challenge to our understanding of brown adipose tissue (BAT) is the lack of an animal model that faithfully represents human BAT. Such a model is essential for direct assessment of the function and therapeutic potential of BAT depots in humans. In human adults, most of the thermoactive BAT depots are located in the supraclavicular region of the neck, while mouse studies focus on depots located in the interscapular region of the torso. We recently discovered BAT depots that are located in a region analogous to that of human supraclavicular BAT (scBAT). Here, we report that the mouse scBAT depot has morphological characteristics of classical BAT, possesses the potential for high thermogenic activity, and expresses a gene signature that is similar to that of human scBAT. Taken together, our studies reveal a mouse BAT depot that represents human BAT and provides a unique tool for developing new translatable approaches for utilizing human scBAT.
Qianxing Mo, Jordan Salley, Tony Roshan, Lisa A. Baer, Francis J. May, Eric J. Jaehnig, Adam C. Lehnig, Xin Guo, Qiang Tong, Alli M. Nuotio-Antar, Farnaz Shamsi, Yu-Hua Tseng, Kristin I. Stanford, Miao-Hsueh Chen
Microglia play a critical role in the development and homeostasis of the CNS. While mobilization of microglia is critical for a number of pathologies, understanding of the mechanisms of their migration in vivo is limited and often based on similarities to macrophages. Kindlin3 deficiency as well as Kindlin3 mutations of integrin-binding sites abolish both integrin inside-out and outside-in signaling in microglia, thereby resulting in severe deficiencies in cell adhesion, polarization, and migration in vitro, which are similar to the defects observed in macrophages. In contrast, while Kindlin3 mutations impaired macrophage mobilization in vivo, they had no effect either on the population of microglia in the CNS during development or on mobilization of microglia and subsequent microgliosis in a model of multiple sclerosis. At the same time, acute microglial response to laser-induced injury was impaired by the lack of Kindlin3-integrin interactions. Based on 2-photon imaging of microglia in the brain, Kindlin3 is required for elongation of microglial processes toward the injury site and formation of phagosomes in response to brain injury. Thus, while Kindlin3 deficiency in human subjects is not expected to diminish the presence of microglia within CNS, it might delay the recovery process after injury, thereby exacerbating its complications.
Julia Meller, Zhihong Chen, Tejasvi Dudiki, Rebecca M. Cull, Rakhilya Murtazina, Saswat K. Bal, Elzbieta Pluskota, Samantha Stefl, Edward F. Plow, Bruce D. Trapp, Tatiana V. Byzova
Memory Th2 cell responses underlie the development and perpetuation of allergic diseases. Because these states result from immune dysregulation, established Th2 cell responses represent a significant challenge for conventional immunotherapies. New approaches that overcome the detrimental effects of immune dysregulation are required. We tested whether memory Th2 cell responses were silenced using a therapeutic approach where allergen expression in DCs is transferred to sensitized recipients using BM cells as a vector for therapeutic gene transfer. Development of allergen-specific Th2 responses and allergen-induced airway inflammation was blocked by expression of allergen in DCs. Adoptive transfer studies showed that Th2 responses were inactivated by a combination of deletion and induction of T cell unresponsiveness. Transfer of BM encoding allergen expression targeted to DCs terminated, in an allergen-specific manner, Th2 responses in sensitized recipients. Importantly, when preexisting airway inflammation was present, there was effective silencing of Th2 cell responses, airway inflammation was alleviated, and airway hyperreactivity was reversed. The effectiveness of DC-targeted allergen expression to terminate established Th2 responses in sensitized animals indicates that exploiting cell-intrinsic T cell tolerance pathways could lead to development of highly effective immunotherapies.
Jane AL-Kouba, Andrew N. Wilkinson, Malcolm R. Starkey, Rajeev Rudraraju, Rhiannon B. Werder, Xiao Liu, Soi-Cheng Law, Jay C. Horvat, Jeremy F. Brooks, Geoffrey R. Hill, Janet M. Davies, Simon Phipps, Philip M. Hansbro, Raymond J. Steptoe
The placebo effect is a phenomenon in which patients who are given an inactive treatment (e.g., inert pill) show a perceived or actual improvement in a medical condition. Placebo effects in clinical trials have been investigated for many years especially because placebo treatments often serve as the control arm of randomized clinical trial designs. Recent observations suggest that placebo effects may be modified by genetics. This observation has given rise to the term “placebome,” which refers to a group of genome-related mediators that affect an individual’s response to placebo treatments. In this study, we conduct a network analysis of the placebome and identify a placebome module in the comprehensive human interactome using a seed-connector algorithm. The placebome module is significantly enriched with neurotransmitter signaling pathways and brain-specific proteins. We validate the placebome module using a large cohort of the Women’s Genome Health Study (WGHS) trial and demonstrate that the placebome module is significantly enriched with genes whose SNPs modify the outcome in the placebo arm of the trial. To gain insights into placebo effects in different diseases and drug treatments, we use a network proximity measure to examine the closeness of the placebome module to different disease modules and drug target modules. The results demonstrate that the network proximity of the placebome module to disease modules in the interactome significantly correlates with the strength of the placebo effect in the corresponding diseases. The proximity of the placebome module to molecular pathways affected by certain drug classes indicates the existence of placebo-drug interactions. This study is helpful for understanding the molecular mechanisms mediating the placebo response, and sets the stage for minimizing its effects in clinical trials and for developing therapeutic strategies that intentionally engage it.
Rui-Sheng Wang, Kathryn T. Hall, Franco Giulianini, Dani Passow, Ted J. Kaptchuk, Joseph Loscalzo
Mechanical ventilation is necessary to support patients with acute lung injury, but also exacerbates injury through mechanical stress–activated signaling pathways. We show that stretch applied to cultured human cells, and to mouse lungs in vivo, induces robust expression of metallothionein, a potent antioxidant and cytoprotective molecule critical for cellular zinc homeostasis. Furthermore, genetic deficiency of murine metallothionein genes exacerbated lung injury caused by high tidal volume mechanical ventilation, identifying an adaptive role for these genes in limiting lung injury. Stretch induction of metallothionein required zinc and the zinc-binding transcription factor MTF1. We further show that mouse dietary zinc deficiency potentiates ventilator-induced lung injury, and that plasma zinc levels are significantly reduced in human patients who go on to develop acute respiratory distress syndrome (ARDS) compared with healthy and non-ARDS intensive care unit (ICU) controls, as well as with other ICU patients without ARDS. Taken together, our findings identify a potentially novel adaptive response of the lung to stretch and a critical role for zinc in defining the lung’s tolerance for mechanical ventilation. These results demonstrate that failure of stretch-adaptive responses play an important role in exacerbating mechanical ventilator–induced lung injury, and identify zinc and metallothionein as targets for lung-protective interventions in patients requiring mechanical ventilation.
Francis Boudreault, Miguel Pinilla-Vera, Joshua A. Englert, Alvin T. Kho, Colleen Isabelle, Antonio J. Arciniegas, Diana Barragan-Bradford, Carolina Quintana, Diana Amador-Munoz, Jiazhen Guan, Kyoung Moo Choi, MICU Registry, Lynette Sholl, Shelley Hurwitz, Daniel J. Tschumperlin, Rebecca M. Baron
Fibrosis results from the dysregulation of tissue repair mechanisms affecting major organ systems, leading to chronic extracellular matrix buildup, and progressive, often fatal, organ failure. Current diagnosis relies on invasive biopsies. Noninvasive methods today cannot distinguish actively progressive fibrogenesis from stable scar, and thus are insensitive for monitoring disease activity or therapeutic responses. Collagen oxidation is a universal signature of active fibrogenesis that precedes collagen crosslinking. Biochemically targeting oxidized lysine residues formed by the action of lysyl oxidase on collagen with a small-molecule gadolinium chelate enables targeted molecular magnetic resonance imaging. This noninvasive direct biochemical elucidation of the fibrotic microenvironment specifically and robustly detected and staged pulmonary and hepatic fibrosis progression, and monitored therapeutic response in animal models. Furthermore, this paradigm is translatable and generally applicable to diverse fibroproliferative disorders.
Howard H. Chen, Philip A. Waghorn, Lan Wei, Luis F. Tapias, Daniel T. Schühle, Nicholas J. Rotile, Chloe M. Jones, Richard J. Looby, Gaofeng Zhao, Justin M. Elliott, Clemens K. Probst, Mari Mino-Kenudson, Gregory Y. Lauwers, Andrew M. Tager, Kenneth K. Tanabe, Michael Lanuti, Bryan C. Fuchs, Peter Caravan
Degenerative cervical myelopathy (DCM) is the most common progressive nontraumatic spinal cord injury. The most common recommended treatment is surgical decompression, although the optimal timing of intervention is an area of ongoing debate. The primary objective of this study was to assess whether a delay in decompression could influence the extent of ischemia-reperfusion injury and alter the trajectory of outcome in DCM. Using a DCM mouse model, we show that decompression acutely led to a 1.5- to 2-fold increase in levels of inflammatory cytokines within the spinal cord. Delayed decompression was associated with exacerbated reperfusion injury, astrogliosis, and poorer neurological recovery. Additionally, delayed decompression was associated with prolonged elevation of inflammatory cytokines and an exacerbated peripheral monocytic inflammatory response (P < 0.01 and 0.001). In contrast, early decompression led to resolution of reperfusion-mediated inflammation, neurological improvement, and reduced hyperalgesia. Similar findings were observed in subjects from the CSM AOSpine North America and International studies, where delayed decompressive surgery resulted in poorer neurological improvement compared with patients with an earlier intervention. Our data demonstrate that delayed surgical decompression for DCM exacerbates reperfusion injury and is associated with ongoing enhanced levels of cytokine expression, microglia activation, and astrogliosis, and paralleled with poorer neurological recovery.
Pia M. Vidal, Spyridon K. Karadimas, Antigona Ulndreaj, Alex M. Laliberte, Lindsay Tetreault, Stefania Forner, Jian Wang, Warren D. Foltz, Michael G. Fehlings
Using transcriptional profiling of platelets from patients presenting with acute myocardial infarction, we identified myeloid-related protein-14 (MRP-14, also known as S100A9) as an acute myocardial infarction gene and reported that platelet MRP-14 binding to platelet CD36 regulates arterial thrombosis. However, whether MRP-14 plays a role in venous thrombosis is unknown. We subjected WT and Mrp-14–deficient (Mrp-14-/-) mice to experimental models of deep vein thrombosis (DVT) by stasis ligation or partial flow restriction (stenosis) of the inferior vena cava. Thrombus weight in response to stasis ligation or stenosis was reduced significantly in Mrp-14-/- mice compared with WT mice. The adoptive transfer of WT neutrophils or platelets, or the infusion of recombinant MRP-8/14, into Mrp-14-/- mice rescued the venous thrombosis defect in Mrp-14-/- mice, indicating that neutrophil- and platelet-derived MRP-14 directly regulate venous thrombogenesis. Stimulation of neutrophils with MRP-14 induced neutrophil extracellular trap (NET) formation, and NETs were reduced in venous thrombi harvested from Mrp-14-/- mice and in Mrp-14-/- neutrophils stimulated with ionomycin. Given prior evidence that MRP-14 also regulates arterial thrombosis, but not hemostasis (i.e., reduced bleeding risk), MRP-14 appears to be a particularly attractive molecular target for treating thrombotic cardiovascular diseases, including myocardial infarction, stroke, and venous thromboembolism.
Yunmei Wang, Huiyun Gao, Chase W. Kessinger, Alvin Schmaier, Farouc A. Jaffer, Daniel I. Simon
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