低氧條件下T細胞衰竭的驅動因素
作者:
小柯機器人發布時間:2021/1/6 16:46:04
美國匹茲堡大學Greg M. Delgoffe研究團隊揭示在缺氧條件下持續刺激引起的線粒體應激快速驅動T細胞衰竭。2021年1月4日出版的《自然-免疫學》雜誌發表了這項成果。
當腫瘤內衰竭T細胞經歷嚴重缺氧時,他們假設代謝應激會改變其對其他信號的反應,特別是持續的抗原刺激。在體外,儘管單獨經歷連續刺激或缺氧的CD8 + T細胞分化為功能性效應物,但這種組合迅速驅動了與衰竭一致的T細胞功能障礙。連續刺激促進了Blimp-1介導的PGC-1α依賴性線粒體重編程阻遏作用,使細胞對缺氧的反應較差。線粒體功能的喪失產生了無法耐受的活性氧(ROS)水平,足以促進衰竭狀態,部分原因是通過磷酸酶抑制和隨後活化T細胞核因子的活性。減少T細胞固有的ROS和降低腫瘤缺氧限制了T細胞衰竭,與免疫療法協同作用。
因此,免疫信號和代謝信號之間存在內在聯繫:通過減輕代謝壓力,可以改變T細胞分化,從而促進更多的功能性細胞命運。
據悉,癌症和慢性感染引起T細胞衰竭,這是一種功能低下的命運,具有明顯的表觀遺傳學、轉錄組學和代謝特徵。但是,衰竭的驅動程序仍然知之甚少。
附:英文原文
Title: Mitochondrial stress induced by continuous stimulation under hypoxia rapidly drives T cell exhaustion
Author: Nicole E. Scharping, Dayana B. Rivadeneira, Ashley V. Menk, Paolo D. A. Vignali, B. Rhodes Ford, Natalie L. Rittenhouse, Ronal Peralta, Yiyang Wang, Yupeng Wang, Kristin DePeaux, Amanda C. Poholek, Greg M. Delgoffe
Issue&Volume: 2021-01-04
Abstract: Cancer and chronic infections induce T cell exhaustion, a hypofunctional fate carrying distinct epigenetic, transcriptomic and metabolic characteristics. However, drivers of exhaustion remain poorly understood. As intratumoral exhausted T cells experience severe hypoxia, we hypothesized that metabolic stress alters their responses to other signals, specifically, persistent antigenic stimulation. In vitro, although CD8+ T cells experiencing continuous stimulation or hypoxia alone differentiated into functional effectors, the combination rapidly drove T cell dysfunction consistent with exhaustion. Continuous stimulation promoted Blimp-1-mediated repression of PGC-1α-dependent mitochondrial reprogramming, rendering cells poorly responsive to hypoxia. Loss of mitochondrial function generated intolerable levels of reactive oxygen species (ROS), sufficient to promote exhausted-like states, in part through phosphatase inhibition and the consequent activity of nuclear factor of activated T cells. Reducing T cell–intrinsic ROS and lowering tumor hypoxia limited T cell exhaustion, synergizing with immunotherapy. Thus, immunologic and metabolic signaling are intrinsically linked: through mitigation of metabolic stress, T cell differentiation can be altered to promote more functional cellular fates.
DOI: 10.1038/s41590-020-00834-9
Source: https://www.nature.com/articles/s41590-020-00834-9