Maturation of immune response to insulin. Recruitment of new epitopes by antibodies.
Guinea pigs were immunized with regular insulin in Freund's adjuvant weekly (N = 6) or with NPH insulin daily (N = 10). The concentrations, the affinities, and the sizes of the insulin-immunoglobin G (IgG) antibody complexes were determined by ultracentrifugation. During the immune response to insulin, 7-S complexes were observed after 3 wk, and 10-S complexes were observed after 4 wk (2P less than .05 in each group). "7-S" antibodies were transferred into immunized guinea pigs before the formation of measurable antibody concentrations. The development of 10-S structures was enhanced in outbred Pirbright white guinea pigs (2P less than .05, N = 6) and in inbred strain II l.b.m. guinea pigs (2P less than .05, N = 7). Insulin may act as a monovalent antigen (7 S) after 3 wk and become bivalent after 4 wk (10 S). The change in valency is enhanced by antibody transfer. It reflects the formation of antibodies recognizing new epitopes on insulin.
D000818:Animals; D000917:Antibody Formation; D000939:Epitopes / Q000276:immunology*; D005260:Female; D006168:Guinea Pigs; D006801:Humans; D007114:Immunization; D007074:Immunoglobulin G / Q000276:immunology; D007328:Insulin / Q000276:immunology*; D007330:Insulin Antibodies / Q000276:immunology*
D000939:Epitopes; D007074:Immunoglobulin G; D007328:Insulin; D007330:Insulin Antibodies