Immunogenicity of trivalent DNA vaccine candidate encapsulated in Chitosan-TPP nanoparticles against EV-A71 and CV-A16.

Aim: To develop a trivalent DNA vaccine candidate encapsulated in Chitosan-TPP nanoparticles against hand foot and mouth disease (HFMD) and assess its immunogenicity in mice. Materials & methods: Trivalent plasmid carrying the VP1 and VP2 genes of EV-A71, VP1 gene of CV-A16 was encapsulated in Chitosan-TPP nanoparticles through ionic gelation. In vitro characterization and in vivo immunization studies of the CS-TPP-NPs (pIRES-VP121) were performed. Results: Mice administered with CS-TPP NPs (pIRES-VP121) intramuscularly were observed to have the highest IFN-γ response. Sera from mice immunized with the naked pDNA and CS-TPP-NPs (pIRES-VP121) demonstrated good viral clearance against wild-type EV-A71 and CV-A16 in RD cells. Conclusion: CS-TPP-NPs (pIRES-VP121) could serve as a prototype for future development of multivalent HFMD DNA vaccine candidates.