B cell activation by pokeweed mitogen in cultures of normal peripheral blood lymphocytes depleted of T regulator subsets by treatment with OKT4 and OKT8 monoclonal antibodies.
OKT4+ (T helper/inducer) and OKT8+ (T cytotoxic/suppressor) subsets were depleted from peripheral blood lymphocytes (PBL) by complement-mediated lysis and residual cells examined for responsiveness to pokeweed mitogen (PWM) using a protein A haemolytic plaque assay for immunoglobulin secreting B cells. It was shown that: (1) three cycles of cell killing were required to totally abolish T helper function; (2) OKT4- PBL did not respond to PWM, but in a co-culture system, an equal number of unfractionated normal PBL could entirely reconstitute responsiveness of the residual B cells; (3) OKT8- PBL gave enhanced numbers of PWM-induced plaque forming cells (PFC); (4) addition of 4 micrograms/ml concanavalin A (con A) to PWM stimulated OKT8- PBL failed to suppress PFC generation, but suppression was induced by 12.5 and 25 micrograms/ml con A and (5) kinetics of PWM-induced PFC development were similar in the presence or absence of OKT8+ cells.
D000328:Adult; D000911:Antibodies, Monoclonal / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology*; D002469:Cell Separation; D002478:Cells, Cultured; D003208:Concanavalin A / Q000494:pharmacology; D006462:Hemolytic Plaque Technique; D006801:Humans; D007070:Immunoglobulin A / Q000032:analysis; D007074:Immunoglobulin G / Q000032:analysis; D007075:Immunoglobulin M / Q000032:analysis; D008213:Lymphocyte Activation; D008212:Lymphocyte Depletion; D011043:Pokeweed Mitogens / Q000494:pharmacology; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology; D050378:T-Lymphocytes, Regulatory / Q000276:immunology
D000911:Antibodies, Monoclonal; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D011043:Pokeweed Mitogens; D003208:Concanavalin A