Division of Medicine, University College London, London, UK.
Núcleo de Doenças Infecciosas, Universidade Federal do Espírito Santo, Vitoria, Brazil.
Aging Cell. 2020 Dec;19(12):e13272. doi: 10.1111/acel.13272. Epub 2020 Nov 9.
The development of senescence in tissues of different organs and in the immune system are usually investigated independently of each other although during ageing, senescence in both cellular systems develop concurrently. Senescent T cells are highly inflammatory and secrete cytotoxic mediators and express natural killer cells receptors (NKR) that bypass their antigen specificity. Instead they recognize stress ligands that are induced by inflammation or infection of different cell types in tissues. In this article we discuss data on T cell senescence, how it is regulated and evidence for novel functional attributes of senescent T cells. We discuss an interactive loop between senescent T cells and senescent non-lymphoid cells and conclude that in situations of intense inflammation, senescent cells may damage healthy tissue. While the example for immunopathology induced by senescent cells that we highlight is cutaneous leishmaniasis, this situation of organ damage may apply to other infections, including COVID-19 and also rheumatoid arthritis, where ageing, inflammation and senescent cells are all part of the same equation.
尽管在衰老过程中，两种细胞系统的衰老同时发生，但不同器官组织中的衰老和免疫系统中的衰老通常是相互独立进行研究的。衰老的 T 细胞具有高度炎症性，并分泌细胞毒性介质，表达自然杀伤细胞受体（NKR），从而绕过其抗原特异性。相反，它们识别由炎症或不同类型细胞感染引起的应激配体。在本文中，我们讨论了关于 T 细胞衰老的数据，它是如何被调控的，以及衰老 T 细胞的新功能属性的证据。我们讨论了衰老 T 细胞和衰老非淋巴细胞之间的交互循环，并得出结论，在炎症强烈的情况下，衰老细胞可能会损害健康组织。虽然我们强调的由衰老细胞引起的免疫病理学的例子是皮肤利什曼病，但这种器官损伤的情况可能适用于其他感染，包括 COVID-19 和类风湿性关节炎，其中衰老、炎症和衰老细胞都是同一等式的一部分。
