title: Increased ability of peripheral blood B cells from patients with rheumatoid arthritis to produce interleukin 1 in vitro.
abstract: Twenty-four patients with rheumatoid arthritis (RA) and 20 normal controls were examined for the ability of their peripheral blood B cells to produce interleukin 1 (IL-1) with or without lipopolysaccharide (LPS). B cells were purified from peripheral blood by negative selection methods (i.e., removal of adherent cells and sheep red blood cell rosette-forming cells, followed by treatment with monoclonal antibodies (OKT3 and OKM1) and complement). The amount of IL-1 in B cell culture supernatants (SN) was measured by thymocyte and fibroblast proliferation assays and an enzyme-linked immunosorbent assay for IL-1 alpha and beta. As a group, cultured B cells from patients with RA, both spontaneously and when stimulated with LPS, produced higher levels of IL-1 than those from normal controls. IL-1 production by RA B cells with LPS had a weak but positive correlation with disease activity. Moreover, RA B cell culture SN with elevated levels of IL-1 had a synergistic effect on the growth of anti-human IgM (anti-mu) stimulated B cells. In separate experiments, the growth of RA B cells was significantly promoted by IL-1 beta both with and without anti-mu stimulation. These results suggest that B cell-derived IL-1 may be involved in the B cell clonal expansion of RA through its own activity as a B cell stimulatory factor.
authors.affiliation: Third Department of Internal Medicine, Okayama University Medical School, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Yamamura
authors.forename: K
authors.initials: K
authors.lastname: Nishiya
authors.forename: Z
authors.initials: Z
authors.lastname: Ota
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000276:immunology*; D001402:B-Lymphocytes / Q000187:drug effects / Q000276:immunology / Q000378:metabolism*; D002455:Cell Division; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007375:Interleukin-1 / Q000096:biosynthesis* / Q000494:pharmacology; D015847:Interleukin-4 / Q000032:analysis; D008070:Lipopolysaccharides / Q000494:pharmacology; D008297:Male; D008875:Middle Aged
chemical_list: D007375:Interleukin-1; D008070:Lipopolysaccharides; D015847:Interleukin-4