Novel SIVmac DNA vaccines encoding Env, Pol and Gag consensus proteins elicit strong cellular immune responses in cynomolgus macaques

Cellular immunity plays an important role in controlling HIV-1 replication. One of the major challenges in developing an HIV-1 DNA vaccine is to generate broader and more potent cellular responses. In this study, we constructed three novel constructs expressing SIVmac antigens Env, Pol and Gag, respectively, with the goal of increasing anti-SIV cellular immunity. The results demonstrate that these constructs can induce strong cellular immune responses in a murine model. Moreover, when applied to cynomolgus macaques, these constructs are not only able to elicit robust IFN-γ effector responses, but also induce SIV antigen-specific CD8+ T cells that have high proliferative capacity. These data suggest that such DNA immunogens deserve further examination for their potential to control viral replication.