Flagellin-PAc fusion protein is a high-efficacy anti-caries mucosal vaccine

We previously demonstrated that an anti-caries dna vaccine intranasally administered with recombinant flagellin protein as a mucosal adjuvant enhanced salivary iga response and conferred better protection against caries. however,the relatively weak immunogenicity of dna vaccines and the necessity for a large quantity of antigens remain significant challenges. here,we fused the flagellin derived from e. coli (kf) and target antigen pac containing the a-p fragment of pac from s. mutans (rpac) to produce a single recombinant protein (kf-rpac). the abilities of kf-rpac to induce rpac-specific mucosal and systemic responses and protective efficiency against caries following intranasal immunization were compared with those of rpac alone or a mixture of rpac and kf (kf + rpac) in rats. results showed that kf-rpac promoted significantly higher rpac-specific antibodies in serum as well as in saliva than did an equivalent dose of rpac alone or a mixture of kf + rpac. intranasal immunization of 8.5 μg kf-rpac could achieve 64.2% reduction of dental caries in rats. in conclusion,our study demonstrated that flagellin and pac fusion strategy is promising for anti-caries vaccine development,and kf-rpac could be used as an anti-caries mucosal vaccine. © 2012 international & american associations for dental research.