Studies in macaques on cross-clade T cell responses elicited by a DNA/MVA AIDS vaccine, better conservation of CD8 than CD4 T cell responses

AIDS Res Hum Retroviruses. 2005 Feb;21(2):140-4. doi: 10.1089/aid.2005.21.140.

Abstract

One of the unknowns faced by an HIV/AIDS vaccine is the ability of a single clade vaccine to protect against the multiple genetic subtypes and recombinant forms of HIV-1 present in the current pandemic. Here, we use a macaque model to investigate the ability of our clade B vaccine that consists of DNA priming and modified vaccinia Ankara (MVA) virus boosting to elicit T cell responses that recognize an A/G recombinant of HIV-1. To test for cross-reactive T cells, intracellular cytokine staining was conducted using five pools of Gag and six pools of Env peptides representing B or A/G sequences. Studies using the peptide pools revealed essentially complete conservation of the CD8 response but only approximately 50% conservation of the CD4 response. Thus, the ability of an HIV vaccine for one clade to protect against other clades may be more limited by the ability to provide CD4 T cell help than the ability to elicit CD8 effector functions.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • AIDS Vaccines / immunology*
  • Animals
  • CD4-Positive T-Lymphocytes / immunology*
  • CD8-Positive T-Lymphocytes / immunology*
  • Cross Reactions
  • HIV-1 / immunology*
  • Macaca
  • Vaccines, DNA / immunology*
  • Vaccines, Synthetic / immunology*
  • Vaccinia virus / immunology

Substances

  • AIDS Vaccines
  • Vaccines, DNA
  • Vaccines, Synthetic