Use of combined immunization routes in induction of a salivary immunoglobulin A response to Streptococcus mutans in Macaca fascicularis monkeys.

Various combinations of immunization routes were examined for ability to elicit or prolong (or both) a salivary secretory immunoglobulin A response to Streptococcus mutans strain Ingbritt (serotype c) in Macaca fascicularis monkeys. Intraductal (i.d.), per os (p.o.), and subcutaneous (s.c.) routes were utilized. Four groups of three to five monkeys each were immunized by the following schedules: group I--p.o., s.c., i.d.; group II--i.d., p.o., i.d.; group III--s.c., p.o., i.d.; and group IV--control. Immune responses in the serum and parotid fluid were quantitated by using passive hemagglutination assays with purified serotype-specific polysaccharide and by indirect immunofluorescent staining assays. Both s.c. and i.d., but not p.o., routes resulted in detectable serum antibody responses. Only i.d. immunization resulted in a measurable salivary response. Indirect immunofluorescent staining revealed specific secretory immunoglobulin A antibodies in the parotid fluid which correlated with passive hemagglutination titers. The p.o. procedures used in this study did not result either in a prolonged immune response or in measurable tolerance related to the humoral or secretory immune system.