Objective:Glucosyltransferase-B (GTF-B) ofStreptococcus mutanshas been implicated as a principal virulent factor in the development of dental caries. The objective was to use recombined plasmid pcDNA-gtfB expressing multiple antigen of glucosyl- transferase-B as gene vaccine to immunize rats through different route, and to investigate the immunization effects of immunization routes.Methods:Atotal of 18 Wistar ratswere divided into 3 groups, including the quadriceps injection group, the intranasal irri- gation group and the submandibular gland-targeted injection group. The serum IgG and salivary IgAwere assayed by using ELISA afterpcDNA3-gtfB immunization. The serum IgG and salivary IgA in different groups were compared using statistical one-way ANOVA.Results:Compared these 3 groups, the serum IgG in the quadriceps injection groupwasmuch higher than those of other two groups (P
