Antibodies to a streptococcal antigen in gingival capillary and crevicular fluid washings, collected from man and non-human primates.

The local gingival antibody response was examined in actively-immunized rhesus monkeys and in human natural immunization to the cell-surface streptococcal antigen (SA I/II). A technique was developed to collect gingival capillary and crevicular fluid washings (GCCFW) from monkeys and human subjects with clinically normal gingiva. The thin crevicular epithelium and the adjacent capillary plexus are pierced with a probe and the resulting mixture of capillary blood, tissue fluid and crevicular fluid are collected by repeated washing of the gingival crevice. Antibodies measured by a solid-phase radioimmunoassay revealed that the IgG class of anti-SA I/II antibodies in GCCFW from the entire gingiva were positively correlated with the corresponding serum antibodies. Antibody levels from six defined dento-gingival units showed a progressive increase in the anti-SA I/II antibody level from the incisor to the premolar and molar units. A significant negative correlation was found between the antibody level of the total GCCFW and past caries experience. A similar negative correlation was found between antibodies from the GCCFW and the DMFS index of the molar teeth. The results are consistent with the hypothesis that there is an independent local immune response in the dento-gingival unit, which is superimposed on the common circulating serum antibodies and sensitized lymphocytes.