Skip to main content

Volume 9 Supplement 2

AIDS Vaccine 2012

Immune control of an SIV challenge by a heterolgous and direct mucosal vaccination regimen in rhesus monkeys


The mucosal surface is the major route for HIV-1 transmission, yet a safe and effective AIDS vaccine through direct mucosal immunization remains elusive.


Here, we report a novel vaccination regimen consisting of a mucosal prime with replication-competent vaccinia Tiantan rMVTTSIVgpe and an intramuscular boost with non-replicating rAd5SIVgpe expressing SIV Gag, Pol and Env. Twenty Chinese rhesus macaques were used to evaluate its safety, immunogenicity and protective potential.


Compared with three control groups, the rMVTTSIVgpe-rAd5SIVgpe regimen elicited robust cellular immune responses with enhanced magnitude, sustainability and polyfunctionality, and higher titers of neutralizing antibodies against SIVmac1A11. Moreover, one rMVTTSIVgpe-rAd5SIVgpe vaccinated animal was fully protected, while the rest demonstrated 1.74-log and 1.2-log reductions in peak and set-point viral loads upon intrarectal challenge with a high dose (5x105 TCID50/animal) of a pathogenic and neutralization-resistant SIVmac239. Importantly, the rMVTTSIVgpe-rAd5SIVgpe vaccinated animals remained healthy up to 850 days post-challenge, while the majority (~75%) of controls progressed to simian AIDS. The protective effect was found to correlate with SIV-specific CD8+ T cell ELIspot responses against Gag and Pol, but not Env.


Our findings indicate that vaccine strategy engaging the mucosal surface from the beginning of vaccination may provide protective immunity against HIV-1 infection in humans.

Author information

Authors and Affiliations


Rights and permissions

Open Access This article is published under license to BioMed Central Ltd. This is an Open Access article is distributed under the terms of the Creative Commons Attribution License ( ), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Reprints and permissions

About this article

Cite this article

Sun, C., Chen, Z., Tang, X. et al. Immune control of an SIV challenge by a heterolgous and direct mucosal vaccination regimen in rhesus monkeys. Retrovirology 9 (Suppl 2), O3 (2012).

Download citation

  • Published:

  • DOI: