title: Isoelectric focusing spectra of anti-bacterial alpha-amylase antibody unique for antigen-induced suppression.
abstract: The effect of intravenous (i.v.) administration of bacterial alpha-amylase (B alpha A) on the IgG antibody response to a subsequent challenge with B alpha A in incomplete Freund's adjuvant (IFA) varied with the difference in responsiveness of the parental strains. High-responder C3H/He (C3) mice given injections of either 200 or 4 micrograms of B alpha A, which alone were unable to trigger a detectable IgG antibody response, generated an enhanced response to an immunogenic challenge given 25 days after the last i.v. injection. The response of low-responder C57BL/6 (B6) mice previously exposed to B alpha A, following a different kinetic course depending on the exposing dose, reached a plateau lower than the levels of control responses (tentatively designated as high- and low-zone suppression). Prior exposure of (B6 X C3)F1 hybrids to 200 micrograms led to the enhanced response, whereas pretreatment with 4 micrograms rendered them partially tolerant to a subsequent challenge. These results suggest that the capacity to achieve low-zone suppression is inherited as a dominant trait. Isoelectric focusing (IEF) analysis revealed that these enhanced responses expanded antibody heterogeneity in a strictly restricted, strain-specific manner as observed during the normal antibody response, although the rate of expansion was accelerated. The specific antibodies produced by individual high-zone suppressed B6 mice were focused as a limited set of bands in a narrow pH range where the specific antibodies produced early in the normal response were focused. In contrast, the response of low-zone suppressed B6 and F1 hybrid mice was characterized by a unique process of heterogeneity expansion.
authors.forename: S
authors.initials: S
authors.lastname: Nakashima
mesh_terms: D000818:Animals; D000942:Antigens, Bacterial / Q000276:immunology*; D001412:Bacillus subtilis / Q000276:immunology; D004306:Dose-Response Relationship, Immunologic; D007108:Immune Tolerance; D007074:Immunoglobulin G / Q000096:biosynthesis*; D007525:Isoelectric Focusing; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D013045:Species Specificity; D000516:alpha-Amylases / Q000276:immunology*
chemical_list: D000942:Antigens, Bacterial; D007074:Immunoglobulin G; D000516:alpha-Amylases