CD4⁺CD28^null T Cells are related to previous cytomegalovirus infection but not to accelerated atherosclerosis in ANCA-associated vasculitis

Previous studies have suggested an increased risk for cardiovascular events in antineutrophil cytoplasmic antibodies (ANCA)-associated vasculitis (AAV). We analyzed the presence of atherosclerotic damage in patients with AAV in relation to the presence of CD4(+)CD28(null) T cells and antibodies against cytomegalovirus (CMV) and human Heat-Shock Protein 60 (hHSP60). In this cross-sectional study, patients with inactive AAV were compared with healthy controls (HC). Carotid intima-media thickness (IMT) and aortic pulse-wave velocity (PWV) were measured. In addition, CD4(+)CD28(null) T cells, anti-CMV, and anti-hHSP60 levels were determined. Forty patients with AAV were included. Patients' spouses were recruited as HC (N = 38). CD4(+)CD28(null) T cells are present in patients with AAV in a higher percentage (median 3.1, range 0.01-85) than in HC (0.28, 0-36, P <0.0001). No significant difference in IMT (mm) between patients and controls was detected (mean 0.77 +/- standard deviation 0.15 and 0.73 +/- 0.11, respectively, P = 0.20). PWV standardized for MAP was increased in AAV patients (9.80 +/- 2.50 m/s, compared to 8.72 +/- 1.68 in HC, P = 0.04). There was a strong association between a previous CMV infection and the presence and percentage of CD4(+)CD28(null) T cells (0.33 vs 13.8, P <0.001). There was no relationship between CD4(+)CD28(null) T cells and/or a previous CMV infection and IMT or PWV. There was no relation between anti-hHSP60 and CD4(+)CD28(null) T cells. Increased PWV values suggest atherosclerotic damage in patients with AAV. Plaque size, as determined by IMT, did not differ. CD4(+)CD28(null) T cells are increased in AAV and related to the previous CMV infection.