Increased CDS‐positive B lymphocytes in type I diabetes

Abstract

CD5+ B lymphocytes have been implicated in the production of polyspecific and monospecific antibodies that bind self‐antigens, and increased proportions of this B cell subset occur in patients with some autoimmune diseases. We investigated the proportion of peripheral blood CD5+ B lymphocytes in type I diabetic patients. Compared with 18 age‐matched healthy subjects. 11 out of 28 (39.2%) type I diabetic patients had increased proportions of circulating CD5+ B lymphocytes with no alterations in the numbers of circulating B and T lymphocytes. Although all patients with increased CD5 B lymphocytes also had serum islet cell antibodies and/or insulin autoantibodies. the occurrence of increased proportions of CD5+ B lymphocytes and scrum autoantibodies was not significantly correlated. Increased proportions of CD5+ B lymphocytes was not related to the time elapsed since the clinical onset of diabetes. In addition, regardless of being increased or normal, the proportion of CD5+ B lymphocytes appeared as a relatively constant phenotype after 1 year of follow‐up studies at 3‐month intervals in eight patients. Although the significance of these findings remains to be established, the possibility exists that CD5+ B cells play a role in the pathogenesis of type I diabetes. Copyright © 1991, Wiley Blackwell. All rights reserved