Differences in specific antibody responses of human tonsillar cells to an oral and a parenteral antigen.

Tonsillar lymphocytes stimulated in vitro with either beta-lactoglobulin or with tetanus toxoid were shown to produce specific antibodies by a direct plaque assay and by radioimmunoprecipitation of the culture supernatants. There was a sixfold increase in the number of IgA-secreting cells in response to beta-lactoglobulin; no such effect was seen in response to tetanus toxoid, where a fivefold rise in IgG-secreting cells occurred. These differences in antibody response are probably due to the route of initial antigen presentation. Those antigens priming the mucosa-associated lymphoid system stimulate mainly IgA-producing cells, in contrast to parenteral antigens, which elicit a predominantly IgM and IgG response.