Research

Elicitation from virus-naive individuals of cytotoxic T lymphocytes directed against conserved HIV-1 epitopes

Pedro A Reche^{* 1,2}, Derin B Keskin^{* 1,2}, Rebecca E Hussey¹, Petronela Ancuta^2,3, Dana Gabuzda^2,3 and Ellis L Reinherz^1,2

¹Laboratory of Immunobiology and Department of Medical Oncology, Dana-Farber Cancer Institute, 44 Binney Street, Boston, MA 02115, USA

²Harvard Medical School, Boston, MA 02115, USA

³Department of Cancer Immunology and AIDS, Dana-Farber Cancer Institute, 44 Binney Street, Boston, MA 02115, USA

Medical Immunology 2006, 5:1doi:10.1186/1476-9433-5-1

Published:	18 May 2006

Abstract

Cytotoxic T lymphocytes (CTL) protect against viruses including HIV-1. To avoid viral escape mutants that thwart immunity, we chose 25 CTL epitopes defined in the context of natural infection with functional and/or structural constraints that maintain sequence conservation. By combining HLA binding predictions with knowledge concerning HLA allele frequencies, a metric estimating population protection coverage (PPC) was computed and epitope pools assembled. Strikingly, only a minority of immunocompetent HIV-1 infected individuals responds to pools with PPC >95%. In contrast, virus-naive individuals uniformly expand IFNγ producing cells and mount anti-HIV-1 cytolytic activity. This disparity suggests a vaccine design paradigm shift from infected to normal subjects.