Effects of local immunization with glucosyltransferase on colonization of hamsters by Streptococcus mutans

Abstract

Experiments were performed to study the effect of antibody to Streptococcus mutans glucosyltransferase (GTF) on the implantation of these organisms in hamsters. Salivary (immunoglobulin A) and serum (immunoglobulin G) antibodies to GTF and GTF-inhibiting activity were elicited by injection of GTF in Freund complete adjuvant in the salivary gland region. Sham-immunized and GTF-immunized groups were then orally challenged with approximately 10(7), 10(8), or 10(9) colony-forming units of cariogenic S. mutans 6715. The results were evaluated by systematically swabbing molars 4 days and approximately 4 weeks after challenge. In general, fewer GTF-immunized hamsters became infected with S. mutans after challenge with 10(7) or 10(8) organisms than did identically challenged sham-immunized hamsters. Of the animals that did become infected, fewer S. mutans colony-forming units were recovered from GTF-immunized hamsters. These results indicate that the presence of antibody to GTF can diminish the ability of S. mutans to implant in the oral cavity of immunized hamsters.