Reactivating latent HIV with PKC agonists induces resistance to apoptosis and is associated with phosphorylation and activation of BCL2

PLoS Pathog. 2020 Oct 19;16(10):e1008906. doi: 10.1371/journal.ppat.1008906. eCollection 2020 Oct.

Abstract

Eradication of HIV-1 by the "kick and kill" strategy requires reactivation of latent virus to cause death of infected cells by either HIV-induced or immune-mediated apoptosis. To date this strategy has been unsuccessful, possibly due to insufficient cell death in reactivated cells to effectively reduce HIV-1 reservoir size. As a possible cause for this cell death resistance, we examined whether leading latency reversal agents (LRAs) affected apoptosis sensitivity of CD4 T cells. Multiple LRAs of different classes inhibited apoptosis in CD4 T cells. Protein kinase C (PKC) agonists bryostatin-1 and prostratin induced phosphorylation and enhanced neutralizing capability of the anti-apoptotic protein BCL2 in a PKC-dependent manner, leading to resistance to apoptosis induced by both intrinsic and extrinsic death stimuli. Furthermore, HIV-1 producing CD4 T cells expressed more BCL2 than uninfected cells, both in vivo and after ex vivo reactivation. Therefore, activation of BCL2 likely contributes to HIV-1 persistence after latency reversal with PKC agonists. The effects of LRAs on apoptosis sensitivity should be considered in designing HIV cure strategies predicated upon the "kick and kill" paradigm.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apoptosis / drug effects*
  • CD4-Positive T-Lymphocytes / virology
  • HIV Infections / drug therapy
  • HIV Infections / virology*
  • HIV-1 / pathogenicity*
  • Humans
  • Phosphorylation
  • Protein Kinase C / chemistry*
  • Protein Kinase C / metabolism
  • Proto-Oncogene Proteins c-bcl-2 / metabolism
  • Virus Activation / drug effects
  • Virus Latency / drug effects*
  • bcl-Associated Death Protein / metabolism

Substances

  • Proto-Oncogene Proteins c-bcl-2
  • bcl-Associated Death Protein
  • Protein Kinase C