Abstract:Toll-like receptor (TLRs) is a pattern recognition receptor expressed in many different types of cells. It plays an important role in cellular inflammatory response, signal transduction and immune surveillance. By recognizing a large variety of ligands, TLRs triggers myeloid differentiation factor 88 (MyD88)-dependent and independent pathways of myeloid cells, leading to the activation of pro-inflammatory cytokines and costimulatory molecules, thus inducing local inflammatory response. The occurrence of autoimmune diseases is related to the abnormality of immune cells and their factors. Several studies have determined that TLR7 is involved in the occurrence and development of rheumatoid arthritis (RA). This article reviews the research progress of TLR7 and its involvement in RA pathogenesis to provide new ideas and theoretical basis for the diagnosis and treatment of the disease.