The striking observation of our study on Exposed Seronegative (ES) is the extraordinarily low levels of HIV-1 DNA. We then applied our improved PCR technology to the SIV-macaque model and demonstrated parallel evidence for low levels of SIV infection and homogeneity of viral sequences in macaques that were transiently viremic or that appeared to be protected from infection by vaccination when tested with conventional assays. All macaques remain healthy for up to 10 years without any sign of progressive infection (still alive). This is remarkable since macaques infected with SIV strains (SIVmne) typically developed simian AIDS and died from AIDS in 1-2 years. The overall goal of this project is to define the mechanisms that may account for the unique control of SIV infection at such low levels. Findings from this project, together with our studies in ES, should provide important information for the control of HIV/SIV infection and vaccine development.
