Increased Circulating CD5+ B Cells in Human SLE: No Correlation with the Level of Autoantibodies

Abstract

There has been a controversy about the association of the levels of CD5+ B cell subpopulation and autoantibodies in SLE. To date, there have been very few papers which compared the levels of the subpopulation with several kinds of autoantibodies. In the present work, we studied the correlations between the levels of circulating CD5+ B cells and autoantibodies against dsDNA, ssDNA, RNA, thyroglobulin, and human lgG in 14 Korean patients with systemic lupus erythematosus (SLE). The levels of circulating CD5+ B cells and total lgM in the sera were also compared in peripheral bloods of these patients and normal individuals. The patients had remarkably elevated levels of both circulating CD5+ B cell subsets and titers of several autoantibodies as compared with normals. A close association of the levels of CD5+ B cell subsets with the measures of any

autoantibodies, however, was not observed. The levels of total lgM in the patients

increased as compared with normal individuals. Our data indicate that the overally increased production of autoantibodies in these patients is due to a polyclonal B-cell activation, not to a specific stimulation of CD5+ B cell subsets.