ABSTRACT
Rheumatoid arthritis [RA] is a chronic inflammatory condition that affects multiple joints. Chemokines and their receptors are involved together in the development and perpetuation of inflammation Chemokine receptors CXCR3 and CXCR4 are among the main regulators of T cell recruitment in autoimmune diseases. The present study aimed at detection of the frequency of CXCR3 and CXCR4 chemokine receptors expression on peripheral blood T-lymphocytes in patients with rheumatoid arthritis in an attempt to identify suitable targets for therapeutic intervention. Twenty eight patients with rheumatoid arthritis, selected from those attending the Rheumatology and Rehabilitation outpatient clinic, Ain Shams University Hospitals, were studied. Ten age and sex matched healthy subjects were served as controls. All patients were subjected to full medical history, thorough clinical examination, evaluation of the disease activity using disease activity score 28 [DAS28] and radiological assessment by plain X rays of both hands and feet [posterior - antero views] for the erosive changes. Peripheral blood lymphocytes analysis was performed by flow cytometry using anti-CD3, anti-CXCR3 and anti-CXCR4 monoclonal antibodies. High statistically significant difference was determined between patients and controls as regard relative count of T- lymphocytes expressing CXCR4 receptors [35.068 +/- 5.098, 23.59 +/- 4.601, respectively and P< 0.001]. Also, there was a significant positive correlation between relative count of T- lymphocytes expressing CXCR4 receptors and disease activity using disease activity sore 28 [DAS28] disease duration and the hemoglobin level. On the other hand, no significant correlation was determined between relative count of T- lymphocytes expressing CXCR3 receptors and any of the clinical and laboratory parameters of patients. Increased expression of CXCR4 on peripheral T cells of Patients [RA Patients] and its positive correlation with the disease activity indicate that this chemokine receptor plays a central role in the process of chronic inflammation in RA and suggests that targeting CXCR4 could provide a new treatment for this disease. Although our data did not prove that CXCR3 expression is higher in patients with RA, however, it can be expected that it is involved in the inflammatory process based on reported functional studies