Immunogenicity of Recombinant DNA Vaccine Encoding Non-Structural Protein-1 Dengue Virus Serotype-2 in Balb/c Mice

Abstract

Dengue Hemorrhagic Fever (DHF) is an infectious disease caused by the dengue virus (DENV) which spread widely in tropical and subtropical regions of the world. DENV is a single-positive strand RNA virus with a genome size of ± 11kb which encodes three structural proteins, seven non-structural proteins, and two untranslated regions (UTR). The non-structural protein-1 (NS1) of DENV is known to have important role in dengue pathogenesis also promising to be developed as dengue vaccine. Lately, novel vaccine approach by DNA immunization have given new perspective for a safe, stable, and immunogenic vaccine platform. Previously, we had successfully constructed DNA vaccine encoding NS1 protein of DENV2 (pUNS1) which expressed recombinant NS1 protein in mammalian cells line. Thus, in this current study the ability of pUNS1 to induce humoral immune response will be further analyzed by in mice immunization. Sixteen BALB/c mice aged of 4 weeks were immunized 3 times with 100 µg of pUNS1 or pUMVC4a on 2 weeks interval. Blood sampling was carried out just before immunization and termination was done 2 weeks after last immunization. Antibodies titer from individual mice sera against DENV-2 were measured with in-house ELISA. Anti-dengue NS1 IgG titer from mice group immunized with recombinant pUNS1 Showed ELISA absorbances five times higher than pUMVC4a group. This result suggested the ability of pUNS1 to induce humoral immune response against NS1 DENV-2 in-vivo. Recombinant pUNS1 can induce humoral immune response in mice.