A chemical genetics approach for studies of HIV-1 latency

项目总结

PROJECT SUMMARY Elimination of integrated, replication-competent HIV-1 proviruses from host genomes persisting despite suppressive anti-retroviral therapy (ART) is the major roadblock to a functional cure. Cells harboring these types of proviruses produce marginal levels of viral products thereby becoming refractory to immune surveillance mechanisms. This lack of detection by the immune system, in addition to its increased growth potential, due to homeostatic proliferation and clonal expansion, extend the lifespan of latently infected cells generating a persistent reservoir. There is enormous enthusiasm for the potential of precision therapies targeting the latent reservoir in clinical settings. To achieve this major biomedical goal, we must first discover host factors dictating reservoir persistence and viral latency maintenance and reactivation before we can leverage this knowledge for clinical intervention. While previous studies have used several genetic approaches to examine host factor’s involvement, they hold the intrinsic problem of not allowing to distinguish between direct and indirect effects. This is a significant issue because one must first define the host factor’s primary function(s) in HIV-1 latency control to then illuminate the most appropriate approaches for therapeutic intervention. In this exploratory and developmental R21 grant application, we circumvent previous issues by implementing a novel chemical genetics (dTAG) approach to acutely eliminate the expression of a set of host chromatin regulators (Histone Lysine Methyl Transferases) to assess their roles in HIV-1 proviral latency maintenance and reactivation. We will first endogenously tag these factors in CD4+ T cell models of latency that recapitulate the biology of viral persistence in patients. We will then select prioritized candidates for cross- validation in primary CD4+ T cell models of latency and aviremic patient samples obtained from the UT Southwestern/Parkland HIV-1 Clinic. If successful, our studies will fill a void in our understanding of HIV-1 latency biology by describing new basic science and elucidating the most appropriate Histone Lysine Methyl Transferases for pilot translational studies. Future studies beyond the scope of this focused grant application will examine the clinical relevance of these host chromatin regulators and devise appropriate therapeutic interventions.