Tracking episomal HIV DNA: implications for viral persistence and eradication of HIV

In this review, methods with which investigators detect and monitor HIV persistence will be described. In particular, we will focus on the work that provides evidence that low-level virus replication persists despite the suppressive effects of therapy and the approaches that can be employed to measure and characterize the ongoing virus replication in apparently aviremic individuals.

With the effectiveness of antiretroviral therapy, there is a need for assays to probe the nature of reservoirs that are maintained despite therapy and to assess the impact of intensification on their stability. Detection and quantitation of surrogate markers for ongoing replication (two long terminal repeat circles) have recently been used to monitor the effects of therapy intensification, source of viral rebound, and characterization of viral variants that contribute to treatment failure.

With successful antiviral therapy, increasingly more attention has turned to the ultimate goal of virus eradication. In order to assess the effectiveness of new therapies and eradication strategies, an assay that can be broadly applied is needed. Amplification of unintegrated DNA is an approach that should be considered to study the effects of therapy intensification and protocols designed to eliminate the reservoirs that persist in HIV-infected individuals.