BACKGROUND: Cell mediated immunity, especially cytotoxic T cell responses against HIV-1 infection, plays a critical role in controlling viral replication and disease progression. DNA vaccine is a novel technology which is known to stimulate strong cellular immune responses. Many DNA vaccines have been tested for HIV infection but there is still no effective vaccine against this infection. Construction of a vaccine consisting of multiple conserved and immunogenic epitopes may increase vaccine efficacy. OBJECTIVE: In the present study a DNA vaccine candidate constructed from HIV-1 P24-Nef was evaluated and cellular immune responses were assessed in murine BALB/c model. METHODS: HIV-1 P24-Nef gene was cloned in PCDNA3.1 expression vector. Mice were immunized with DNA construct and IL-4 and IFN-gamma evaluation was performed using ELISPOT. Cytotoxicity response was evaluated with Granzyme B ELISPOT assay and lymphocyte proliferation was evaluated with LTT assay. RESULTS: Analysis of immune responses showed that, compared to control groups, the candidate vaccine induced production of higher levels of both IL-4 and IFN-gamma (p<0.05). Cytotoxicity and lymphocyte proliferation responses of mice vaccinated with the candidate vaccine were significantly increased compared to control groups (p<0.05). CONCLUSION: HIV-1 P24-Nef DNA construct displayed strong immunogenicity in a murine model.
BACKGROUND: Cell mediated immunity, especially cytotoxic T cell responses against HIV-1 infection, plays a critical role in controlling viral replication and disease progression. DNA vaccine is a novel technology which is known to stimulate strong cellular immune responses. Many DNA vaccines have been tested for HIV infection but there is still no effective vaccine against this infection. Construction of a vaccine consisting of multiple conserved and immunogenic epitopes may increase vaccine efficacy. OBJECTIVE: In the present study a DNA vaccine candidate constructed from HIV-1 P24-Nef was evaluated and cellular immune responses were assessed in murine BALB/c model. METHODS:HIV-1 P24-Nef gene was cloned in PCDNA3.1 expression vector. Mice were immunized with DNA construct and IL-4 and IFN-gamma evaluation was performed using ELISPOT. Cytotoxicity response was evaluated with Granzyme B ELISPOT assay and lymphocyte proliferation was evaluated with LTT assay. RESULTS: Analysis of immune responses showed that, compared to control groups, the candidate vaccine induced production of higher levels of both IL-4 and IFN-gamma (p<0.05). Cytotoxicity and lymphocyte proliferation responses of mice vaccinated with the candidate vaccine were significantly increased compared to control groups (p<0.05). CONCLUSION:HIV-1 P24-Nef DNA construct displayed strong immunogenicity in a murine model.