Critical role for Env as well as Gag-Pol in control of a simian-human immunodeficiency virus 89.6P challenge by a DNA prime/recombinant modified vaccinia virus Ankara vaccine.

Journal Article (Journal Article)

Cellular immune responses against epitopes in conserved Gag and Pol sequences of human immunodeficiency virus type 1 have become popular targets for candidate AIDS vaccines. Recently, we used a simian-human immunodeficiency virus model (SHIV 89.6P) with macaques to demonstrate the control of a pathogenic mucosal challenge by priming with Gag-Pol-Env-expressing DNA and boosting with Gag-Pol-Env-expressing recombinant modified vaccinia virus Ankara (rMVA). Here we tested Gag-Pol DNA priming and Gag-Pol rMVA boosting to evaluate the contribution of anti-Env immune responses to viral control. The Gag-Pol vaccine raised frequencies of Gag-specific T cells similar to those raised by the Gag-Pol-Env vaccine. Following challenge, these rapidly expanded to counter the challenge infection. Despite this, the control of the SHIV 89.6P challenge was delayed and inconsistent in the Gag-Pol-vaccinated group and all of the animals underwent severe and, in most cases, sustained loss of CD4(+) cells. Interestingly, most of the CD4(+) cells that were lost in the Gag-Pol-vaccinated group were uninfected cells. We suggest that the rapid appearance of binding antibody for Env in Gag-Pol-Env-vaccinated animals helped protect uninfected CD4(+) cells from Env-induced apoptosis. Our results highlight the importance of immune responses to Env, as well as to Gag-Pol, in the control of immunodeficiency virus challenges and the protection of CD4(+) cells.

Full Text

Duke Authors

Cited Authors

  • Amara, RR; Smith, JM; Staprans, SI; Montefiori, DC; Villinger, F; Altman, JD; O'Neil, SP; Kozyr, NL; Xu, Y; Wyatt, LS; Earl, PL; Herndon, JG; McNicholl, JM; McClure, HM; Moss, B; Robinson, HL

Published Date

  • June 2002

Published In

Volume / Issue

  • 76 / 12

Start / End Page

  • 6138 - 6146

PubMed ID

  • 12021347

Pubmed Central ID

  • PMC136190

International Standard Serial Number (ISSN)

  • 0022-538X

Digital Object Identifier (DOI)

  • 10.1128/jvi.76.12.6138-6146.2002


  • eng

Conference Location

  • United States