In vivo activation of latent HIV with a synthetic bryostatin analog effects both latent cell "kick" and "kill" in strategy for virus eradication

PLoS Pathog. 2017 Sep 21;13(9):e1006575. doi: 10.1371/journal.ppat.1006575. eCollection 2017 Sep.

Abstract

The ability of HIV to establish a long-lived latent infection within resting CD4+ T cells leads to persistence and episodic resupply of the virus in patients treated with antiretroviral therapy (ART), thereby preventing eradication of the disease. Protein kinase C (PKC) modulators such as bryostatin 1 can activate these latently infected cells, potentially leading to their elimination by virus-mediated cytopathic effects, the host's immune response and/or therapeutic strategies targeting cells actively expressing virus. While research in this area has focused heavily on naturally-occurring PKC modulators, their study has been hampered by their limited and variable availability, and equally significantly by sub-optimal activity and in vivo tolerability. Here we show that a designed, synthetically-accessible analog of bryostatin 1 is better-tolerated in vivo when compared with the naturally-occurring product and potently induces HIV expression from latency in humanized BLT mice, a proven and important model for studying HIV persistence and pathogenesis in vivo. Importantly, this induction of virus expression causes some of the newly HIV-expressing cells to die. Thus, designed, synthetically-accessible, tunable, and efficacious bryostatin analogs can mediate both a "kick" and "kill" response in latently-infected cells and exhibit improved tolerability, therefore showing unique promise as clinical adjuvants for HIV eradication.

MeSH terms

  • Anti-HIV Agents / pharmacology*
  • Bryostatins / chemistry
  • Bryostatins / pharmacology*
  • CD4-Positive T-Lymphocytes / virology*
  • HIV Infections / drug therapy
  • HIV Infections / immunology
  • HIV-1 / drug effects*
  • HIV-1 / isolation & purification
  • Humans
  • Virus Activation / drug effects
  • Virus Latency / drug effects*

Substances

  • Anti-HIV Agents
  • Bryostatins
  • bryostatin 1