Abstract: Objective:To investigate the expression levels of chemokine receptor CXCR4 and its ligand SDF-1α in peripheral blood of patients with rheumatoid arthritis.Methods:Fifty-two patients with rheumatoid arthritis and 30 healthy people were divided into the observation group and control group,respectively.The levels of CXCR4,SDF-1α and IL-8 in peripheral blood of two groups were measured.Results:The expression rates of CXCR4 on the surface of CD3⁺CD4⁺ and CD3⁺CD8⁺ T lymphocytes,and levels of SDF-1α and IL-8 in peripheral blood of observation group were significantly higher than those in control group(P<0.05).With the prolonging of disease course,the expression rates of CXCR4 on the surface of CD3⁺CD4⁺ and CD3⁺CD8⁺ T lymphocytes,and level of SDF-1α in peripheral blood of observation group increased(P<0.05).Linear correlation analysis showed that the expression levels of CXCR4 and SDF-1α were positive correlation with IL-8 in peripheral blood(P<0.05).Conclusions:The signal transduction pathway of SDF-1α/CXCR4 and IL-8 may be involved in the pathogenesis and progression of rheumatoid arthritis.