title: Inhibitory effect of anti-class II antibodies on human B-cell activation.
abstract: The role of class II antigens for B-cell activation was analyzed using purified human B cells and anti-class II monoclonal antibodies. The stimulation of purified B cells with Staphylococcus aureus Cowan I induced proliferation and differentiation into immunoglobulin-producing cells in the presence of interleukin-1 and T-cell-derived factors (B-cell growth factor and B-cell differentiation factor). The addition of anti-class II monoclonal antibodies inhibited B-cell responses. However, anti-class I monoclonal antibody did not inhibit B-cell responses. When mitomycin C and cycloheximide-treated B cells were added to the induction culture of B cells as the stimulator, B-cell responses were enhanced in a dose-dependent manner. Furthermore, the stimulator B cells also partially restored the suppressed B-cell responses which were induced by the pretreatment of B cells with anti-class II antibody. This enhancing effect of stimulator B cells on B-cell responses was inhibited by the pretreatment of stimulator B cells with anti-class II antibody. The treatment of B cells with anti-class II antibody and complement depleted the activity of both responder B cells and stimulator B cells. These results suggest that cellular interaction among B cells exists in the B-cell activation induced with Staphylococcus aureus, Cowan I and anti-class II antibody inhibits B-cell activation by interfering in this cellular interaction.
authors.affiliation: First Department of Internal Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Tanaka
authors.forename: F
authors.initials: F
authors.lastname: Shirakawa
authors.forename: T
authors.initials: T
authors.lastname: Ota
authors.forename: H
authors.initials: H
authors.lastname: Suzuki
authors.forename: S
authors.initials: S
authors.lastname: Eto
authors.forename: U
authors.initials: U
authors.lastname: Yamashita
mesh_terms: D001402:B-Lymphocytes / Q000145:classification / Q000276:immunology* / Q000502:physiology; D002450:Cell Communication; D002454:Cell Differentiation; D004306:Dose-Response Relationship, Immunologic; D006681:HLA-D Antigens / Q000032:analysis / Q000276:immunology*; D006801:Humans; D007166:Immunosuppressive Agents / Q000502:physiology*; D007518:Isoantibodies / Q000502:physiology*; D007700:Kinetics; D008213:Lymphocyte Activation; D013209:Staphylococcal Vaccines / Q000276:immunology
chemical_list: D006681:HLA-D Antigens; D007166:Immunosuppressive Agents; D007518:Isoantibodies; D013209:Staphylococcal Vaccines