Enhancement of antibody production by a learning paradigm.

The experiments described here show that production of serum antibody to a defined protein antigen (hen egg-white lysozyme) can be elicited by classical Pavlovian conditioning in Wistar rats. Reexposure of animals to a gustatory conditioned stimulus that had previously been paired with antigen induces a reliable increase in antibody production. This conditioned production of antibodies of IgM and IgG isotypes is similar to that found in secondary responses elicited by reinjection of antigen. These findings demonstrate that the immune system can be stimulated to produce apparently normal antibody responses by a simple behavioral paradigm.