title: Isolation of a rabbit IgG fraction with cytophilic properties.
abstract: About 15% of rabbit IgG loaded on a column of Con A-Sepharose 4B was found to be specifically bound to the column due to a structural variation in its carbohydrate moiety. The Con A-retained rabbit IgG contained a higher amount of neutral hexoses than the initial IgG but its molecular weight, antigenic structure and half-life were identical or similar. The Con A-retained rabbit IgG has an affinity for the Fc receptor-bearing homologous macrophages which is 10 times higher than that of the initial IgG. The IgG fraction not retained on Con A-Sepharose is practically devoid of binding ability. These results suggest that the Con A-bound IgG may represent the cytophilic fraction of monomeric IgG responsible for the binding of IgG to Fc receptor-bearing cells.
mesh_terms: D000818:Animals; D000915:Antibody Affinity; D002846:Chromatography, Affinity; D007074:Immunoglobulin G / Q000302:isolation & purification*; D008264:Macrophages / Q000378:metabolism*; D011817:Rabbits; D011961:Receptors, Fc / Q000032:analysis*; D017452:Receptors, IgG; D012397:Rosette Formation; D012685:Sepharose / Q000031:analogs & derivatives / Q000378:metabolism; D012756:Sheep; D013552:Swine
chemical_list: D007074:Immunoglobulin G; D011961:Receptors, Fc; D017452:Receptors, IgG; C028326:concanavalin A-sepharose; D012685:Sepharose