The role of T cells in IgG production; thymus-dependent antigens induce B cell memory in the absence of T cells.
B cell memory was shown to develop in congenitally athymic (nu/nu) mice after injection with small amounts of thymus-dependent antigens, in particular heterologous serum proteins, such as fown gamma-globulin (FGG) or DNP-bovine-serum albumin (DNP-BSA). Large doses of proteins (10 mg) tended to produce a specific B cell unresponsiveness, although there was still some evidence of B cell priming. The antigen did not have to be in a multivalent form to interact with B cell so as to induce immunologic memory or tolerance. In contrast to the induction of B cell memory, the production of IgG antibody in this system was found to be strongly T cell dependent. Thymus-independent antigens like LPS or POL with pronounced adjuvant effects on IgG production in normal or surgically thymectomized mice, could not replace T cells in allowing an IgG response against thymus-dependent antigens in congenitally athymic mice. However, the action of T cells once activated is likely to be non-antigen-specific, since it was shown that supernatants of antigen-activated-syngeneic T cells stimulated IgG production in cultures of primed B cell populations non-antigen-specifically.
D000818:Animals; D000917:Antibody Formation; D000921:Antibody-Producing Cells; D001402:B-Lymphocytes / Q000276:immunology*; D001853:Bone Marrow / Q000276:immunology; D001854:Bone Marrow Cells; D002645:Chickens / Q000276:immunology; D004926:Escherichia coli / Q000276:immunology; D005408:Flagellin; D006462:Hemolytic Plaque Technique; D006801:Humans; D007074:Immunoglobulin G; D007156:Immunologic Memory; D008070:Lipopolysaccharides; D051379:Mice; D008819:Mice, Nude; D011135:Polysaccharides, Bacterial; D011828:Radiation Chimera; D012475:Salmonella / Q000276:immunology; D012486:Salmonella typhimurium / Q000276:immunology; D012710:Serum Albumin, Bovine; D013601:T-Lymphocytes / Q000276:immunology*; D013934:Thymectomy; D013950:Thymus Gland / Q000276:immunology*; D005719:gamma-Globulins
D007074:Immunoglobulin G; D008070:Lipopolysaccharides; D011135:Polysaccharides, Bacterial; D005719:gamma-Globulins; D005408:Flagellin; D012710:Serum Albumin, Bovine