Standardized assessment of NAb responses elicited in rhesus monkeys immunized with single- or multi-clade HIV-1 envelope immunogens.

Journal Article (Journal Article)

The genetic diversity of HIV-1 envelope glycoproteins (Env) remains a major obstacle to the development of an antibody-based AIDS vaccine. The present studies examine the breadth and magnitude of neutralizing antibody (NAb) responses in rhesus monkeys after immunization with DNA prime-recombinant adenovirus (rAd) boost vaccines encoding either single or multiple genetically distant Env immunogens, and subsequently challenged with a pathogenic simian-human immunodeficiency virus (SHIV-89.6P). Using a standardized multi-tier panel of reference Env pseudoviruses for NAb assessment, we show that monkeys immunized with a mixture of Env immunogens (clades A, B, and C) exhibited a greater breadth of NAb activity against neutralization-sensitive Tier 1 viruses following both vaccination and challenge compared to monkeys immunized with a single Env immunogen (clade B or C). However, all groups of Env-vaccinated monkeys demonstrated only limited neutralizing activity against Tier 2 pseudoviruses, which are more characteristic of the neutralization sensitivity of circulating HIV-1. Notably, the development of a post-challenge NAb response against SHIV-89.6P was similar in monkeys receiving either clade B, clade C, or clade A+B+C Env immunogens, suggesting cross-clade priming of NAb responses. In addition, vaccines encoding Env immunogens heterologous to SHIV-89.6P primed for a rapid anamnestic NAb response following infection compared to vaccines lacking an Env component. These results show that DNA/rAd immunization with multiple diverse Env immunogens is a viable approach for enhancing the breadth of NAb responses against HIV-1, and suggest that Env immunogens can prime for anamnestic NAb responses against a heterologous challenge virus.

Full Text

Duke Authors

Cited Authors

  • Seaman, MS; Leblanc, DF; Grandpre, LE; Bartman, MT; Montefiori, DC; Letvin, NL; Mascola, JR

Published Date

  • October 10, 2007

Published In

Volume / Issue

  • 367 / 1

Start / End Page

  • 175 - 186

PubMed ID

  • 17599382

Pubmed Central ID

  • PMC2075526

International Standard Serial Number (ISSN)

  • 0042-6822

Digital Object Identifier (DOI)

  • 10.1016/j.virol.2007.05.024


  • eng

Conference Location

  • United States