Mucosal Administration Of GTF Proteins Induces Protective Response.(glucosyltransferase helps to protect against dental caries)

2001 SEP 19 - (NewsRx.com & NewsRx.net) --

by N.R. Saltmarsh, staff medical writer - Mucosal administration of peptide-based Streptococcus mutans glucosyltransferase (GTF) vaccines can induce immune responses that are potentially protective against dental caries, researchers in the United States have found.

If combined with the CT or LT R192G mucosal adjuvant, GTF vaccine facilitated mucosal and systemic immunity to S. mutans glucosyltransferase, reported D.J. Smith and colleagues at the Forsyth Institute, Boston.

"Synthetic peptide vaccines which are derived from functional domains of S. mutans GTF have been shown to induce protective immunity in Sprague-Dawley rats after subcutaneous injection in the salivary gland region," noted Smith and associates.

Since mucosal induction of salivary immunity would be preferable in humans, the researchers studied several methods of facilitating the immune response: incorporating peptides in bioadhesive poly(D,L-lactide-coglycolide) (PLGA) microparticles, monoepitopic (HDS) or diepitopic (HDS-GLU) peptide constructs, or mucosal adjuvants.

"Salivary immunoglobulin A (IgA) responses were not detected after intranasal administration of diepitopic HDS-GLU peptide constructs in alum or after incorporation into PLGA microparticles," reported Smith and coworkers. "However, significant primary and secondary salivary IgA and serum IgG antibody responses to HDS were induced in all rats when cholera holotoxin (CT) or a detoxified mutant Escherichia coli heat-labile enterotoxin (R192G LT) were intranasally administered with HDS peptide constructs in PLGA."

Coadministration of LT with HDS resulted in predominantly IgG2a responses in the serum, while coadministration of CT and HDS stimulated significant IgG1 and IgG2a ...