Suppressive effect of mizoribine on humoral antibody production in DBA/2 mice.
The mode of action of mizoribine (MZR) as a B cell inhibitor was studied using DBA/2 mice. Its in vitro administration significantly delayed the primary response in hemagglutinin production against sheep erythrocytes by suppressing the IgM antibody formation. In vitro plaque-forming cell (PFC) response against both T-dependent and T-independent antigens, such as TNP-SRBC and TNP-Brucella abortus, was dose-dependently suppressed by MZR. Since PFC formation by the T-depleted fraction of splenocytes was likewise suppressed, MZR may inhibit humoral antibody response by directly affecting the B cells (and/or macrophages) as well as by modulating the regulatory T cells. MZR may only act on a certain stage of the cell cycle of B lymphocytes following antigenic stimulation. It may not interfere with the initial antigen recognition or with mature B cells.
D000818:Animals; D000917:Antibody Formation / Q000187:drug effects*; D001402:B-Lymphocytes / Q000187:drug effects; D002453:Cell Cycle / Q000187:drug effects; D004912:Erythrocytes / Q000276:immunology; D005260:Female; D007165:Immunosuppression Therapy; D008211:Lymphocyte Cooperation / Q000187:drug effects; D008264:Macrophages / Q000187:drug effects; D051379:Mice; D008811:Mice, Inbred DBA / Q000276:immunology; D008814:Mice, Inbred NZB / Q000276:immunology; D012263:Ribonucleosides / Q000494:pharmacology*; D013154:Spleen / Q000276:immunology; D013601:T-Lymphocytes / Q000187:drug effects; D014301:Trinitrobenzenes / Q000276:immunology
D012263:Ribonucleosides; D014301:Trinitrobenzenes; C010052:mizoribine