title: Rapid recovery of helper activity following T cell depleted allogeneic marrow transplant.
abstract: Within the first year after T cell depleted bone marrow transplantation, co-cultures of T cells and non-T cells from 32 individual recipients examined on 43 occasions generally failed to produce increased quantities of immunoglobulin in response to stimulation with pokeweed mitogen or B cell differentiation factors. Failure occurred even in the presence of significant numbers of CD20 + ve B cells. The non-production of Ig appears to be due to a functional B cell defect, since adding marrow donor (syngeneic) T cells to recipient B cells in the presence of PWM or conditioned medium did not lead to immunoglobulin production. This B cell deficit persisted for 1 year. In contrast helper activity in the recipient T cell enriched population returns rapidly and by 6 weeks after transplant co-cultures of marrow donor B cells and recipient T cells produce comparable amounts of Ig to co-cultures of donor T and B cells. This prolonged defect of B cell function in vitro correlates with a year long delay before humoral responses to novel vaccine antigens can be elicited in vivo.
mesh_terms: D000293:Adolescent; D000328:Adult; D001402:B-Lymphocytes / Q000276:immunology*; D016026:Bone Marrow Transplantation; D002648:Child; D005260:Female; D006801:Humans; D007108:Immune Tolerance; D007074:Immunoglobulin G / Q000096:biosynthesis; D007075:Immunoglobulin M / Q000096:biosynthesis; D008213:Lymphocyte Activation; D008211:Lymphocyte Cooperation; D008212:Lymphocyte Depletion; D008297:Male; D011043:Pokeweed Mitogens / Q000494:pharmacology; D013601:T-Lymphocytes / Q000276:immunology; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*
chemical_list: D007074:Immunoglobulin G; D007075:Immunoglobulin M; D011043:Pokeweed Mitogens