作者: de Bruijn, Beaunelle ; Boshuizen, Julia ; Lin, Chun-Pu ; van Vliet, Alex ; Visser, Nils L ; Apriamashvili, Georgi ; Besser, Michal J ; van Hal-van Veen, Susan E ; Huinen, Zowi R ; Ligtenberg, Maarten A ; Sinha, Sanju ; Simon Nieto, Juan ; Markel, Gal ; Markovits, Ettai ; Vredevoogd, David W ; Altelaar, Maarten ; Bleijerveld, Onno B ; Levy, Pierre L ; Peeper, Daniel S ; Díaz-Gómez, Judit ; Ruppin, Eytan ; Sánchez, Santiago Duro ; Krijgsman, Oscar

BackgroundBlockade of the programmed cell death protein 1 (PD-1) immune checkpoint (ICB) is revolutionizing cancer therapy, but little is known about the mechanisms governing its expression on CD8 T cells. Because PD-1 is induced during activation of T cells, we set out to uncover regulators whose inhibition suppresses PD-1 abundance without adversely impacting on T cell activation.MethodsTo identify PD-1 regulators in an unbiased fashion, we performed a whole-genome, fluorescence-activated cell sorting (FACS)-based CRISPR-Cas9 screen in primary murine CD8 T cells. A dual-readout design using the activation marker CD137 allowed us to uncouple genes involved in PD-1 regulation from those governing general T cell activation.ResultsWe found that the inactivation of one of several members of the TMED/EMP24/GP25L/p24 family of transport proteins, most prominently TMED10, reduced PD-1 cell surface abundance, thereby augmenting T cell activity. Another client protein was cytotoxic T lymphocyte-associated protein 4 (CTLA-4), which was also suppressed by TMED inactivation. Treatment with TMED inhibitor AGN192403 led to lysosomal degradation of the TMED-PD-1 complex and reduced PD-1 abundance in tumor-infiltrating CD8 T cells (TIL) in mice, thus reversing T cell dysfunction. Clinically corroborating these findings, single-cell RNA analyses revealed a positive correlation between TMED expression in CD8 TIL, and both a T cell dysfunction signature and lack of ICB response. Similarly, patients receiving a TIL product with high TMED expression had a shorter overall survival.ConclusionOur results uncover a novel mechanism of PD-1 regulation, and identify a pharmacologically tractable target whose inhibition suppresses PD-1 abundance and T cell dysfunction.

2017-06-01·European Journal of Pharmacology3区 · 医学

Further analysis of the inhibition by agmatine on the cardiac sympathetic outflow: Role of the α 2 -adrenoceptor subtypes

3区 · 医学

Article

作者: Aguayo-Morales, Hilda ; Chin-Chan, Miguel ; Cobos-Puc, Luis ; Ventura-Sobrevilla, Janeth ; Luque-Contreras, Diana

This study has investigated the role of the α₂-adrenoceptor subtypes involved in the inhibition of the cardiac sympathetic outflow induced by intravenous (i.v) infusions of agmatine. Therefore, we analysed the effect of an i.v. bolus injections of the selective antagonists BRL 44408 (300μg/kg; α_2A), imiloxan (3000μg/kg; α_2B), and JP-1302 (300μg/kg; α_2C) given separately, and their combinations: BRL 44408 plus Imiloxan, JP 1302 plus imiloxan, BRL 44408 plus JP-1302, BRL 44408 plus imiloxan plus JP-1302 on the cardiac sympatho-inhibition of agmatine. Also, the effect of the combination BRL 44408 plus JP-1302 plus AGN 192403 (3000μg/kg; I₁ antagonist) was evaluated. In this way, i.v. infusions of 1000μg/kg min of agmatine, but not 300, inhibited the tachycardic response induced by electrical stimulation. Furthermore, the antagonists used or their combinations had no effect on the electrically-induced tachycardic response. On the other hand, the inhibitory response of agmatine was: (1) partially antagonized by BRL 44408 or JP-1302 given separately, a similar response was observed when we administered their combination with imiloxan, but not by imiloxan alone, (2) antagonized in greater magnitude by the combination BRL 44408 plus JP-1302 or the combination BRL 44408 plus imiloxan plus JP-1302, and (3) abolished by the combination BRL 44408 plus JP-1302 plus AGN 192403. Taken together, these results demonstrate that the α_2A- and α_2C-adrenoceptor subtypes and I₁-imidazoline receptors are involved in the inhibition of the cardiac sympathetic outflow induced by agmatine.

2014-09-01·Brain Research Bulletin3区 · 医学

Evidence for the gastric cytoprotective effect of centrally injected agmatine

3区 · 医学

Article

作者: Zádori, Zoltán S ; Németh, József ; Fehér, Ágnes ; Philipp, Kirsch ; Tóth, Viktória E ; Gyires, Klára

Agmatine (decarboxylated arginine) exerts cytoprotective action in several tissues, such as in the brain, heart or kidneys, but there is still controversy over the effects of agmatine on the gastric mucosa. The aim of the present study was to reveal the potential gastroprotective action of agmatine by using an acid-independent ulcer model to clarify which receptors and peripheral factors are involved in it. Gastric mucosal damage was induced by acidified ethanol. Mucosal levels of calcitonin gene-related peptide (CGRP) and somatostatin were determined by radioimmunoassay. For analysis of gastric motor activity the rubber balloon method was used. It was found that agmatine given intracerebroventricularly (i.c.v., 0.044-220 nmol/rat) significantly inhibited the development of ethanol-induced mucosal damage, while in the case of intraperitoneal injection (0.001-50mg/kg i.p.) it had only a minor effect. The central gastroprotective action of agmatine was completely antagonized by mixed alpha2-adrenoceptor and imidazoline I1 receptor antagonists (idazoxan, efaroxan), but only partially by yohimbine (selective alpha2-adrenoceptor antagonist) and AGN 192403 (selective I1 receptor ligand, putative antagonist). It was also inhibited by the non-selective opioid-receptor antagonist naloxone and the selective δ-opioid receptor antagonist naltrindole, but not by β-funaltrexamine and nor-Binaltorphimine (selective μ- and κ-opioid receptor antagonists, respectively). Furthermore, the effect of agmatine was antagonized by bilateral cervical vagotomy and by pretreatment with indomethacin and NG-nitro-l-arginine. Agmatine also reversed the ethanol-induced reduction of gastric mucosal CGRP and somatostatin content, but did not have any significant effect on gastric motor activity. These results indicate that agmatine given centrally induces gastric cytoprotection, which is mediated by central imidazoline I1 receptors, alpha2-adrenoceptors and δ-opioid receptors. Activation of these receptors induces the release of different mucosal protective factors, such as NO, prostaglandins, CGRP and somatostatin by a vagal-dependent mechanism. Alterations of gastric motility are not likely to contribute to the observed protective effect.

100 项与 AGN 192403 相关的药物交易

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