Increase in specific antibody-forming cells in human tonsils after oral stimulation with D-53, a ribosomal vaccine.

Thirty subjects who had received an oral ribosomal vaccine to common bacteria of upper respiratory tract infections, and ten controls were tonsillectomized for recurrent infections or rhonchologic pathology. A three-step indirect immunofluorescence technique was used to identify and enumerate specific antibody forming cells (SAFC) in their tonsils. Plasma-cells specific of the four strains being constituents of the oral vaccine (H. influenzae, K. pneumoniae, S. pyogenes and S. pneumoniae) were observed in all samples. The numbers of SAFC were significantly higher in the subjects who had received the oral vaccine. These results support the efficiency or oral immunization in increasing local defenses, even at distance from the sensitized gut-associated lymphoid tissue. These data provide evidence for the homing phenomenon in human mucosae associated lymphoid tissue (MALT).