IgA antibodies in rat bile inhibit cholera toxin-induced secretion in ileal loops in situ

• Published in: Immunology Vol. 55; no. 4; pp. 579 - 583
• Main Authors: TAMARU, T, BROWN, W. R
• Format: Journal Article
• Language: English
• Published: Oxford Blackwell 01-08-1985
• Subjects: Animals; Antibodies, Bacterial - immunology; Applied sciences; Bile - immunology; Cholera Toxin - administration & dosage; Cholera Toxin - immunology; Enzyme-Linked Immunosorbent Assay; Exact sciences and technology; Ileum - secretion; Immunoglobulin A, Secretory - analysis; Immunoglobulin A, Secretory - immunology; Male; Other techniques and industries; Rats; Rats, Inbred Strains
• ISSN: 0019-2805; 1365-2567

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.