Regulation of Homocytotropic Antibody Formation in the Rat

Abstract

Adult rats about 3 months old were splenectomized or thymectomized and then immunized with dinitrophenylated Ascaris suum extracts (DNP-As) plus Bordetella pertussis 3 to 10 days after the operation. Homocytotropic antibody (HTA) formation against DNP-As was examined by passive cutaneous anaphylaxis (PCA) over a period of 45 days. HTA formation was found to be greatly enhanced and prolonged by splenectomy and thymectomy. Virtually no termination of HTA formation occurred. Combined extirpation of the spleen and thymus in adult rats had the same enhancing effect. Passive hemagglutination tests with sera treated or untreated with 2-mercaptoethanol showed that the production of γG and γM antibodies was unchanged. In contrast to adult thymectomy, neonatal thymectomy caused a loss, or at least a marked reduction, of the ability to produce HTA. The results suggest that adult splenectomy and thymectomy cause regulatory disturbances of HTA formation in the rat.