To increase the immunogenicity and efficacy of DNA vaccines, several approaches have been conducted, including using chemical adjuvants [104, 105] , co-administrating plasmids expressing cytokines [106, 107] , modifying the targeted G protein [108, 109] , increasing the expression level of encoded proteins [94] , co-inoculating with a traditional inactivated rabies vaccine [110] , and optimizing DNA vaccine formulation, such as through targeted trafficking of a G protein to a lysosome supplemented with adjuvant Emulsigen-D [111, 112] .