Cellular And Humoral Immune Responses Induced By HIV-1 Clade C DNA Vaccine

At present,there is not a good measure in control and prevention of HIV infection.In order to control and prevention of HIV infection,the best effectively measure is developing a safe and effective vaccine to prevent HIV infection.DNA vaccine has become one of new strategies for HIV vaccine.It can overcome difficulties of traditional HIV vaccines,for example,pathogenicity in vaccines,restricted specificity of neutralizing antibodies and absence of CTLs.The gag sequences are important gene of structural proteins of HIV and encode core proteins which have relatively constant amino acid sequences.Gag proteins play an important role in replication of HIV.In the study, a recombinant plasmid pVAX-gag (pVAX-gag was given by ADARC,and it was constructed by inserting the HIV-1 clade C gag into a DNA vaccine expression vector pVAX.) was expressed in vitro.Meanwhile, another recombinant plasmid pGEX-gag was constructed by inserting the gag into a expression vector pGEX-5X-l,and recombinant protein Gag was expressed and purified. The expressed products of gag gene from pVAX-gag and pGEX-gag were examined by Western-blot.The result indicated that the recombinant protein could be recognized by anti-p24 monoclonal antibody. Then Balb/C mice were immunized by the recombinant plasmid pVAX-gag,and the cellular immune response of these mice was analyzed by flow cytometer. As a coating antigen , the purified recombinant protein Gag was used in ELISA to evaluate humoral immune response of these mice. As a result,the recombinant plasmid pVAX-gag could effectively induce cellular and humoral immune responses in Balb/C mice. This immunological effects showed positive correlation with immunization dose.The study lay a foundation for development of HIV-1 DNA vaccines in China.