Abstract

Despite three decades of research, the correlates of protective immunity against HIV infection remain poorly defined, which poses a significant barrier to HIV vaccine development. I will present data from immunological and virological studies of two very different village cohorts we have studied in an effort to understand better the factors associated with delayed HIV disease progression.

The first is a remote community in rural Guinea-Bissau which is home to a community cohort of people with HIV -2 infection that has been followed for over 20 years: the majority of HIV -2-infected people behave as long-term non-progressors (LTNPs) and maintain a viral load below detection for many years, whereas the progressors are clinically indistinguishable from progressors with HIV -1.

The second cohort in central China became infected with HIV -1 through a contaminated plasma donor scheme in the mid 1990s that led to infection with a very narrow range of viruses: this scenario allows a clear analysis of the host selection pressures on the infecting virus over time, and shows how much selection is imposed in association with HLA class I and KIR molecules in the infected individuals.