Effect of concanavalin A on lymphocyte interactions involved in the antibody response to type III pneumococcal polysaccharide. II. Ability of suppressor T cells to act on both B cells and amplified T cells to limit the magnitude of the antibody response.
When administered 2 days after immunization with 0.5 microgram Type III pneumococcal polysaccharide (SSS-III), the T lymphocyte mitogen concanavalin A (Con A) stimulates a 2.6-to 7-fold enhancement of the plaque-forming cells (PFC) response to SSS-III in vivo. This enhancement requires the presence of amplified T cells, which act by driving PFC or their precursors to extra rounds of proliferation. The extra proliferation that can be stimulated by Con A is not seen in the normal primary response to SSS-III; but treatment with anti-lymphocyte serum (ALS) to remove suppressor T cells will permit the additional proliferation to occur. This indicates that in the primary response to SSS-III, suppressor T cells act on amplifier T cells to limit the magnitude of the antibody response. Only suppression of B cells can account for the further suppression induced by Con A given at the time of immunization or by low-dose paralysis of the SSS-III response. The relatively late development of amplified activity compared to suppressor activity appears to account for the absence of amplifier activity after primary immunization with SSS-III. It is apparent that one can explain the regulatory effects observed during the development of an immune response to SSS-III only by considering both T cell- B cell and T cell- T cell interactions, together with the temporal relationships involved in those interactions.
D000818:Animals; D000917:Antibody Formation; D001402:B-Lymphocytes / Q000276:immunology; D003208:Concanavalin A / Q000494:pharmacology*; D004306:Dose-Response Relationship, Immunologic; D005260:Female; D006462:Hemolytic Plaque Technique; D007111:Immunity, Cellular; D007165:Immunosuppression Therapy; D007700:Kinetics; D008213:Lymphocyte Activation; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D011135:Polysaccharides, Bacterial / Q000276:immunology*; D013296:Streptococcus pneumoniae / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology; D013997:Time Factors; D014747:Vinblastine / Q000494:pharmacology
D011135:Polysaccharides, Bacterial; D003208:Concanavalin A; D014747:Vinblastine