Role of Toll-like receptor 7 in anti-infective immunity

doi:10.12140/j.issn.1000-7423.2022.01.015

Abstract

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

CLC Number:

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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