Induction of balance and breadth in the immune response is beneficial for the control of SIVmac239 replication in rhesus monkeys

SummaryObjectivesThe aim of this study was to induce cellular and humoral responses with enhanced breadth and more balanced magnitude as a possible approach for an effective HIV vaccine.MethodsAll nine of the SIVmac239 genes (gag, pol, env, nef, vif, vpx, vpr, rev and tat) were optimized for mammalian expression, synthesized and cloned into recombinant adenovirus type 5 (Ad5). These vectors were used as a vaccine regimen, and the immunogenicity and immune protection of this regimen was assessed in murine and macaques.ResultsA vaccine regimen including all nine genes of the SIVmac239 virus was developed, and it was demonstrated that in contrast to single antigen vaccination, the total SIV antigen regimen more effectively elicited the balanced and broad immune responses in murine and macaques. Moreover, the responses afforded effective immune control against infection and replication of the highly pathogenic SIVmac239.ConclusionsInduction of balance and breadth in the immune response is beneficial in controlling SIVmac239 replication in rhesus monkeys. This study provides insight for the future development of an effective HIV vaccine.