title: IgA antibodies in rat bile inhibit cholera toxin-induced secretion in ileal loops in situ.
abstract: The biological actions of IgA antibodies in bile are largely undefined. We therefore tested whether biliary IgA antibodies could specifically inhibit cholera enterotoxin (CT)-induced secretion in the rat ileum. Rats were immunized by CT given orally or by injection into Peyer's patches. Bile was collected by bile duct cannulation, and anti-CT antibodies in the bile were measured by ELISA. CT plus bile from either immunized or unimmunized rats, or CT plus anti-CT-containing bile which had been absorbed by a CT immunosorbent, were instilled into in situ ileal loops in unimmunized rats; CT alone, or buffer was instilled into other loops. The bile used from the immunized rats contained IgA, but neither IgG nor IgM, anti-CT antibodies. It was found that bile containing IgA anti-CT antibodies almost totally inhibited the secretory effect of CT, and this inhibition was abrogated by absorption of the IgA anti-CT antibodies. Thus, IgA antibodies to an enterotoxin, secreted into bile, are effective against the enterotoxin in the rat intestine in vivo.
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000276:immunology*; D001646:Bile / Q000276:immunology*; D002772:Cholera Toxin / Q000008:administration & dosage / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D007082:Ileum / Q000378:metabolism*; D007071:Immunoglobulin A, Secretory / Q000032:analysis / Q000276:immunology*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D000907:Antibodies, Bacterial; D007071:Immunoglobulin A, Secretory; D002772:Cholera Toxin