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 GTFimmunized groups were then orally challenged with approximately 107, 108, or 109 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 107 or 108 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. Studies of the effect of immunization with glucosyltransferase (GTF) from Streptococcus mutans on experimental dental caries have revealed several features of antibody interactions with GTF. In vitro studies have shown that salivary antibody obtained by immunization with GTF from one serotype of S. mutans combines with and inhibits the activity of GTF enzyme from several other serotypes of S. mutans (14, 15). Antibody having specificity for GTF can inhibit in vitro bacterial accumulation on glass surfaces and may alter the composition so that acid may more readily diffuse through these deposits (M. A

Sheep Red Blood Cell Instillation at Palatine Tonsil Effectively Induces Specific IgA Class Antibody in Saliva in Rabbits

“…The methods of antigen administration and their induction of specific IgA in saliva have been studied mainly for the purpose of examining their possible application in the prevention of caries and periodontal disease. They have been injected into salivary glands (25) and administered orally (7,16,21) and nasally (29). This is the first report to our knowledge that specific IgA can be induced in saliva by antigen instillation at the surface of the palatine tonsil.…”

Water-insoluble Glucan Synthesis by Mutans Streptococcal Strains Correlates with Caries Incidence in 12- to 30-month-old Children

“…Interestingly, we have observed a statistically significant positive association between the level of synthesis of WIG by MS clinical isolates and caries incidence (Table 3), suggesting that differences in the activity of GTF could be associated with differing levels of virulence of these S. mutans isolates. The activity of S. mutans GTF-B and GTF-C is associated with significant caries induction in animal models (Yamashita et al, 1993) and with sucrose-dependent adherence on smooth surfaces in vitro and in experimental animals (Tsumori and Kuramitsu, 1997;Smith et al, 1982). Furthermore, induction of immunity against GTF has been associated with cariesprotective effects Hajishengallis and Michalek, 1999;Russell et al, 1999), further implicating this enzyme in the molecular pathogenesis of dental caries.…”

Defense mechanisms involving Fc-dependent functions of immunoglobulin A and their subversion by bacterial immunoglobulin A proteases.

“…The firm establishment of Streptococcus mutans on tooth surfaces can be inhibited by salivary antibodies directed at S. mutans glycosyltransferases, which catalyze the synthesis of extracellular polysaccharides required for the accumulation of the bacterium (42,66). An additional example of enzyme-neutralizing S-IgA antibodies, which may be important in host-parasite relationships, consists of those found in secretions with the ability to inhibit bacterial IgAl proteases (21; see below).…”