title: Increased peripheral blood B-cells expressing the CD5 molecules in association to autoantibodies in patients with lupus erythematosus and evidence to selectively down-modulate them.
abstract: The present investigation has been undertaken to analyze absolute and relative CD5+ B-cell numbers in patients with lupus erythematosus (LE), and concomitant B-CLL, and to monitor them under therapy. Peripheral blood lymphocytes of LE-patients, and healthy controls were analyzed by flow cytometry and direct immunofluorescence technique. Patients were treated with low-dose methotrexate (MTX). Before and during MTX treatment laboratory monitoring has been done. LE-patients had increased percentages of CD5+CD19+ as compared to controls (p < 0.0002), the absolute number of CD5+ B-cells was equal in controls and patients. Autoantibodies were positively correlated to the number of CD5+ B-cells in LE-patients. In a total of 140 LE-patients one male patient suffered from both LE and B-CLL (0.7%). He had increased absolute and relative CD5+ B-cells. MTX induced significant decrease of both total B-cell numbers, and CD5+ B-cells. The decrease of CD5+CD19+ cells was more pronounced than the decrease of total B-cells. Apoptosis rate increased in parallel to the drop-down of elevated CD5+CD19+ cells. Peripheral T-cell subsets remained stable under low-dose MTX. Both absolute and relative numbers of CD5+CD19+ cells should be taken into account in patients with LE. MTX seems to decrease B-cells, and preferentially to down-regulate B-cells expressing the CD5 molecule, which opens new therapeutic options and cell biological activities. The mechanism is unclear but apoptosis induction seems to be likely.
authors.affiliation: Department of Radiology, University of Bonn, Sigmund-Freud Strasse 25, Bonn 53105, Germany. i.boehm@uni-bonn.de
authors.forename: Ingrid
authors.initials: I
authors.lastname: Böhm
mesh_terms: D000328:Adult; D000368:Aged; D001323:Autoantibodies / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology*; D018956:CD5 Antigens / Q000097:blood*; D005260:Female; D005434:Flow Cytometry; D019085:Fluorescent Antibody Technique, Direct; D006801:Humans; D007166:Immunosuppressive Agents / Q000494:pharmacology / Q000627:therapeutic use; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000150:complications; D008180:Lupus Erythematosus, Systemic / Q000150:complications / Q000276:immunology*; D008297:Male; D008727:Methotrexate / Q000627:therapeutic use; D008875:Middle Aged; D012189:Retrospective Studies
chemical_list: D001323:Autoantibodies; D018956:CD5 Antigens; D007166:Immunosuppressive Agents; D008727:Methotrexate