CD28(−) Cells Are Increased in Early Rheumatoid Arthritis and Are Linked With Cytomegalovirus Status

Objective: CD3(+)CD8(+)CD28(−) cells are higher in Rheumatoid Arthritis (RA). The aim of this study was to assess CD3(+)CD8(+)CD28(−) cells in patients with early RA and assess the effects of cytomegalovirus (CMV) seropositivity. Method: In this prospective observation study, 50 RA patients were recruited from Cardiff University Hospital of Wales (UHW) rheumatology outpatient, 25 patients with early disease (disease duration 0–6 months) and 25 patients with established disease (>2 years). These were compared with 25 healthy controls. Clinical and serological markers of inflammation were noted, and peripheral blood mononuclear cells were analyzed using flow cytometry. Results: The percentage of the CD8(+)CD28(−) T cells was increased in RA patients and was associated with disease duration. The percentage of CD8(+)CD28(−) T cells was increased in CMV positive early and established RA grouped and early RA patients in comparison to CMV negative patients (p < 0.05). There is a weak but statistically significant correlation between the percentage of CD3(+)CD8(+)CD28(−) cells and CRP in CMV positive RA patients (r = 0.227, p < 0.05). Conclusion: The percentage of CD8(+)CD28(−) T cells is higher in RA patients and correlates with disease duration, highlighting a potential role early in the disease process. These cells were also higher in CMV positive early RA patients which may suggest a role of CMV in disease development.