Toll样受体7在抗感染免疫中的作用

doi:10.12140/j.issn.1000-7423.2022.01.015

摘要/Abstract

摘要：

Toll样受体7(Toll-like receptor 7,TLR7)是一种模式识别受体,细胞静息状态下主要定位于浆细胞样树突状细胞、巨噬细胞、T淋巴细胞、中性粒细胞等免疫细胞,以及上皮细胞、内皮细胞、角质形成细胞等非免疫细胞的内质网上。病原体感染时,TLR7从内质网转移到效应细胞的内体膜上。TLR7可直接识别单链RNA或核酸类似物等配体,与特异性招募蛋白结合并激活核因子-κB、丝裂原活化蛋白激酶和干扰素等调控因子,从而启动固有免疫应答和适应性免疫应答,参与抗感染免疫。本文就TLR7及其配体的结构与功能、TLR7在抗感染免疫中的作用及其相关信号通路等进行综述,以期为TLR7在抗感染免疫中的作用机制研究提供科学依据。

关键词: Toll样受体7, 抗感染, 免疫应答, 分子机制

Abstract:

Toll-like receptor 7 (TLR7) is a pattern recognition receptor mainly expressed in the endoplasmic reticulum of the resting immune cells including plasmacytoid dendritic cell, mononuclear macrophages, T lymphocytes, neutrophils and non-immune cells including epithelial cells, endothelial cells and keratinocytes. During an infection, TLR7 is translocated to the endosome membrane from endoplasmic reticulum of the host cells. TLR7 can directly recognize single-stranded RNA or nucleic acid analogs and bind to specific recruiting proteins to activate nuclear factor-κB, mitogen-activated protein kinase and interferon regulatory factors, which eventually triggers the innate or adaptive immune response against an infection. Here we have reviewed the structure and function of TLR7 and its ligand, the role of TLR7 against an infection and its signaling pathways to provide the scientific basis for further studies of TLR7 in infection and immunity.

Key words: Toll-like receptor 7, Anti-infection, Immune response, Molecular mechanism

中图分类号:

尹昌竹, 李迪, 蔡娟, 徐红玲, 王灵军, 郑明辉, 刘晖. Toll样受体7在抗感染免疫中的作用[J]. 中国寄生虫学与寄生虫病杂志, 2022, 40(1): 99-103.

YIN Chang-zhu, LI Di, CAI Juan, XU Hong-ling, WANG Ling-jun, ZHENG Ming-hui, LIU Hui. Role of Toll-like receptor 7 in anti-infective immunity[J]. Chinese Journal of Parasitology and Parasitic Diseases, 2022, 40(1): 99-103.

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