Our work aims to understand better the mechanisms that underlie HIV disease progression. The immune system, particularly its T-cell arm, plays a central role in HIV pathogenesis. Our long-term goal is to use the knowledge gained through these studies to develop novel therapeutic approaches. We use multiple nonhuman primate models with differing disease progression courses, and we study T-cell immunology in HIV-infected individuals or SIV-infected nonhuman primates in order to elucidate mechanisms of disease progression. The main areas of research are summarized below.