title: Two biologically different mouse IgG1 antibodies.
abstract: Isolated mouse antibodies were submitted to affinity chromatography with protein A. Three peaks were obtained: peak I that did not bind to protein A, peak II eluted with 0.5 M NaSCN and peak III eluted with 2.0 M NaSCN. Peak I and peak II contained IgG1 but no detectable IgG2 or IgG3, whereas peak III contained IgG2 and IgG3 but no detectable IgG1. Peak I, but not peak II, showed heat-resistant passive cutaneous anaphylactic (PCA) activity in rats which was absorbed by anti-IgG1 antiserum but not by anti-IgE. Both peak I and peak II showed heat-resistant PCA activity in mice, that was absorbed by anti-IgG1 serum. Peak III showed PCA activity in guinea pigs but not in mice or rats. These findings suggest that mouse IgG1 can be divided into 2 populations that differ in their affinity for protein A and in their PCA activity.
mesh_terms: D000818:Animals; D000888:Antibodies, Anti-Idiotypic / Q000276:immunology; D002846:Chromatography, Affinity; D005260:Female; D007073:Immunoglobulin E / Q000276:immunology; D007074:Immunoglobulin G / Q000145:classification* / Q000276:immunology / Q000378:metabolism; D008297:Male; D051379:Mice; D013205:Staphylococcal Protein A / Q000378:metabolism; D013696:Temperature
chemical_list: D000888:Antibodies, Anti-Idiotypic; D007074:Immunoglobulin G; D013205:Staphylococcal Protein A; D007073:Immunoglobulin E