CD19/22 balance relates to improvement of disease activity in systemic lupus erythematosus

B cells in patients with systemic lupus erythematosus (SLE) are hyperactivated and B-cell receptor signal transduction may be affected by various response regulators. CD19 and CD22 play a major role as regulators of B-cell response. Therefore, we examined CD19 and CD22 expressions on B cells of patients with SLE, and how they were related to disease activity. Thirty-one patients with active SLE were selected and enrolled in this study. Evaluation of CD19 and CD22 expressions on B cells was performed prior to and after treatments with flow cytometry analysis. Disease activity was determined according to the SLE disease activity index score. CD19 and CD22 expressions on B cells in SLE patients revealed no significant differences when compared with the controls. However, improvement of SLE was recognized among patients with an increased ratio of CD22-positive cells. Our results suggest that this balance is a useful marker for determining improvement of SLE disease activity, although the CD19/22 balance does not contribute to the pathogenesis of SLE.