Isoform-Selective Versus Nonselective Histone Deacetylase Inhibitors in HIV Latency Reversal

HIV remains incurable due to the persistence of a latent viral reservoir found in HIV-infected cells, primarily resting memory CD4(+) T cells. Depletion of this reservoir may be the only way to end this deadly epidemic. In latency, the integrated proviral DNA of HIV is transcriptionally silenced partly due to the activity of histone deacetylases (HDACs). One strategy proposed to overcome this challenge is the use of HDAC inhibitors (HDACis) as latency reversal agents to induce viral expression (shock) under the cover of antiretroviral therapy. It is hoped that this will lead to elimination of the reservoir by immunologic and viral cytopathic (kill). However, there are 18 isoforms of HDACs leading to varying selectivity for HDACis. In this study, we review HDACis with emphasis on their selectivity for HIV latency reversal.