Expression of Neopterin and Chemokines in Rheumatoid Arthritis and Cardiovascular Disease

Abstract

Abstract In chronic inflammatory processes like rheumatoid arthritis (RA) and cardiovascular diseases (CVD) the role of pteridines and chemokines in the immune response is of great interest. The objectives of the study were to obtain information about an involvement of specific chemokines on the inflammatory process in patients with RA and CVD with activated production of the pteridine neopterin. 113 patients with RA according to American College of Rheumatology criteria including 24.8% suffering from CVD were included in the study (23% male, 77% female). For the assessment of monocyte activation and chemotaxis as well as the proinflammatory influence of chemokines on B-cells and angiogenesis in RA, neopterin and the chemokines CCL2, CXCL13 and CX3CL1 were measured by radio- and enzyme-immunoassays in serum. Neopterin and chemokines were all found in high concentrations. Neopterin significantly correlated with all chemokines: CXCL13 (rs = 0.368; p <0.0001), CX3CL1 (rs = 0.241; p <0.02), CCL2 (rs = 231; p <0.02), demonstrating high neopterin levels in RA patients to have a strong association to the chemokine induced chemotaxis of B-cells (CXCL13) and mononuclear cells (CX3CL1, CCL2). Significantly elevated concentrations of neopterin and CXCL13 were seen in patients with RA plus CVD compared to RA without CVD (p <0.03). The high incidence of cardiovascular diseases in rheumatoid arthritis seems to be associated with enhanced mononuclear (neopterin, CCL2) and B-cell activation (CXCL13), and as a consequence increased immune system activity.