PMID: 19525965
Title: Effective low titer antibody protection against low dose repeated mucosal SHIV challenge in macaques
Abstract: Neutralizing antibodies are thought to be crucial for HIV vaccine protection, but studies in animal models suggest that high antibody concentrations are required. This is a major potential hurdle for vaccine design. However, these studies typically apply a large virus inoculum to ensure infection in control animals in single-challenge experiments. In contrast, most human infection via sexual encounter probably involves repeated exposures to much lower doses of virus. Therefore, animal studies may have provided an overestimate of the levels of antibodies required for protection in humans. We investigated whether plasma concentrations of antibody corresponding to relatively modest neutralization titers in vitro could protect macaques from repeated intravaginal exposure to low doses of a simian immunodeficiency virus-HIV chimera (SHIV) that uses the CC chemokine receptor 5 (CCR5) co-receptor. An effector function-deficient variant of the neutralizing antibody was also included. The results show that a substantially larger number of challenges is required to infect macaques treated with neutralizing antibody than control antibody-treated macaques, and support the notion that effector function may contribute to antibody protection. Overall, the results imply that lower amounts of antibody than previously considered protective may provide benefit in the context of typical human exposure to HIV-1.
Date: 1970-08-21
Year: 2009
Journal: Nat. Med.
PMID Author: Hessell AJ, Poignard P, Hunter M, Hangartner L, Tehrani DM, Bleeker WK, Parren PW, Marx PA, Burton DR
PMC Link #: PMC4334439

Media Contacts

Africa

Ethel Makila
+254 71 904 3142
EMakila@iavi.org

 

Europe

Hester Kuipers
+31 20 521 0343
HKuipers@iavi.org 

 

Global

Anita Kawatra
+1 212 847 1055
AKawatra@iavi.org 

 

India

Saif ul Hadi
+91 11 4737 6032
SulHadi@iavi.org 

 

United States

Rose Catlos
+1 212 847 1049
RCatlos@iavi.org