Induction of secretory antibodies in humans following ingestion of Streptococcus mutans.

1) Ingestion of Streptococcus mutans antigen by human volunteers induced the selective appearance of antibodies in saliva and tears but not in serum. 2) These antibodies were associated with the IgA class as determined by enhanced or blocked agglutination, immunofluorescence and gel filtration. 3) A second series of antigen ingestion resulted in a secondary response in these secretions characterized by an earlier appearance of antibodies which reached higher titers than in the primary response.