Inhibition of the humoral response by spleen cells from cyclophosphamide-treated mice.
Spleen cells obtained from mice injected with cyclophosphamide (200 mg/kg body weight) suppressed the secondary IgG antibody response of memory cells to a T-dependent antigen, DNP-HGG, in Millipore diffusion chambers. Significant suppression (greater than 50%) was found from 5 to 14 days following cyclophosphamide treatment, with peak suppression (86%) on day 7. The primary IgM antibody response to DNP-Ficoll, a T-independent antigen, was not suppressed by these cells. In contrast, suppression was observed in the primary IgM response to sheep red blood cells, a T-dependent antigen. In addition, treatment of the suppressor cell population with anti-Thy-1 serum and complement did not inhibit suppressor activity. We concluded that the suppressor activity was not attributable to a typical T cell, and that the target of suppression was not a B cell. Preliminary evidence suggests that the suppressor activity is regulated, directly or indirectly, by a T cell.
D000818:Animals; D000917:Antibody Formation / Q000187:drug effects; D003520:Cyclophosphamide / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005260:Female; D007075:Immunoglobulin M / Q000096:biosynthesis; D007156:Immunologic Memory / Q000187:drug effects*; D008213:Lymphocyte Activation; D051379:Mice; D013154:Spleen / Q000276:immunology; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*; D013997:Time Factors
D007075:Immunoglobulin M; D003520:Cyclophosphamide