Changes in Immunological and Neuronal Conditions Markedly Altered Antibody Response to Intracerebroventricularly Injected Ovalbumin in the Rat

The serum antibody response to ovalbumin (OA) has been investigated following intracerebroventricular (i.c.v.) and intravenous administration of antigen in the rat, under altered neuronal and immunological conditions. I.c.v. administration of antigen was far more potent in eliciting humoral immune response. Central nervous system (CNS) immunization under the conditions of disrupted blood-brain barrier decreased anti-OA antibody production. Peripheral polyclonal stimulation with Bordetella pertussis increased production of specific antibodies to i.c.v. injected antigen, while complete Freund’s adjuvant had no effect on the immune response. These results suggest that CNS compartmentalization of antigen may be critical for mounting strong antibody production, and that peripheral polyclonal stimulation of the immune system may markedly contribute to the overall intensity of the immune response.