Publications & Reports

Broad neutralization and complement-mediated lysis of HIV-1 by PEHRG214, a novel caprine anti-HIV-1 polyclonal antibody.

Verity EE, Williams LA, Haddad DN, Choy V, O'Loughlin C, Chatfield C, Saksena NK, Cunningham A, Gelder F, McPhee DA
Department of Microbiology, Monash University, Clayton, Victoria, Australia.

Abstract

OBJECTIVES: To assess the potency, breadth of action, and mechanism of action of the polyclonal goat anti-HIV antibody, PEHRG214. DESIGN: Typical human antibody responses to HIV-1 infection are unable to neutralize virus efficiently, clear the infection, or prevent disease progression. However, more potent neutralizing antibodies may be capable of playing a pivotal role in controlling HIV replication in vivo. PEHRG214 is a polyclonal caprine antibody raised against purified HIV-associated proteins, such that epitopes that are immunologically silent in humans may potentially be recognized in another species. It has been administered safely to HIV-infected individuals in Phase I clinical trials. METHODS: The anti-HIV activity of PEHRG214 was assessed using neutralization and virion lysis assays. The target proteins for PEHRG214 activity were investigated using flow cytometry and by adsorption of anti-cell antibodies from the antibody cocktail. RESULTS: PEHRG214 strongly neutralized a diverse range of primary HIV-1 isolates, encompassing subtypes A to E and both CCR5 and CXCR4 phenotypes. Neutralization was enhanced by the presence of complement. PEHRG214 also induced complement-mediated lysis of all HIV-1 isolates tested, and recognized or cross-reacted with a number of host cell proteins. Lysis was abrogated by adsorption with T and/or B cells expressing GPI-linked proteins, but not by GPI-deficient B cells or red blood cells. CONCLUSIONS: PEHRG214 was found to potently neutralize and lyse HIV-1 particles. By targeting host cell proteins present in the viral envelope, which are conserved among all strains tested, PEHRG214 potentially opens up a highly novel means of eliminating circulating virus in infected individuals.

Publication

  • Journal: AIDS
  • Published: 28/02/2006
  • Volume: 20
  • Issue: 4
  • Pagination: 505-515

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