ingenol-dibenzoate and HIV-Infections

Despite the durable viral suppression afforded by antiretroviral therapy, HIV-1 eradication will require strategies to target latently infected cells that persist in infected individuals. Protein kinase C (PKC) activation is a promising strategy to reactivate latent proviruses and allow for subsequent recognition and clearance of infected cells by the immune system. Ingenol derivatives are PKC agonists that induce latency reversal but also lead to T cell activation and the release of pro-inflammatory cytokines, which would be undesirable in vivo. In this work, we sought to identify compounds that would suppress pro-inflammatory cytokine production in the context of PKC activation.. We performed an in vitro screen to identify compounds that could dampen pro-inflammatory cytokine release associated with T cell activation, using IL-6 as a model cytokine. We then tested the ability of the most promising screening hit, the FDA-approved Janus Kinase (JAK) inhibitor ruxolitinib, to diminish release of multiple cytokines and its effect on latency reversal using cells from HIV-1-positive, aviremic participants.. We demonstrate that co-administration of ruxolitinib with ingenol-3,20-dibenzoate significantly reduces pro-inflammatory cytokine release without impairing latency reversal ex vivo.. The combination of ingenol compounds and JAK inhibition represents a novel strategy for HIV-1 eradication.

Topics: Anti-HIV Agents; CD4-Positive T-Lymphocytes; Cytokines; Diterpenes; Drug Evaluation, Preclinical; High-Throughput Screening Assays; HIV Infections; HIV-1; Humans; Interleukin-6; Janus Kinases; Lymphocyte Activation; Nitriles; Protein Kinase C; Pyrazoles; Pyrimidines; Virus Activation; Virus Latency

The human immunodeficiency virus type 1 (HIV-1) latent reservoir in resting CD4(+) T cells represents a major barrier to viral eradication. Small compounds capable of latency reversal have not demonstrated uniform responses across in vitro HIV-1 latency cell models. Characterizing compounds that demonstrate latency-reversing activity in resting CD4(+) T cells from aviremic patients ex vivo will help inform pilot clinical trials aimed at HIV-1 eradication. We have optimized a rapid ex vivo assay using resting CD4(+) T cells from aviremic HIV-1(+) patients to evaluate both the bioactivity and latency-reversing potential of candidate latency-reversing agents (LRAs). Using this assay, we characterize the properties of two candidate compounds from promising LRA classes, ingenol 3,20-dibenzoate (a protein kinase C agonist) and panobinostat (a histone deacetylase inhibitor), in cells from HIV-1(+) antiretroviral therapy (ART)-treated aviremic participants, including the effects on cellular activation and cytotoxicity. Ingenol induced viral release at levels similar to those of the positive control (CD3/28 receptor stimulation) in cells from a majority of participants and represents an exciting LRA candidate, as it combines a robust viral reactivation potential with a low toxicity profile. At concentrations that blocked histone deacetylation, panobinostat displayed a wide range of potency among participant samples and consistently induced significant levels of apoptosis. The protein kinase C agonist ingenol 3,20-dibenzoate demonstrated significant promise in a rapid ex vivo assay using resting CD4(+) T cells from treated HIV-1-positive patients to measure latent HIV-1 reactivation.

Topics: Adult; Anti-HIV Agents; Antiretroviral Therapy, Highly Active; Case-Control Studies; CD4-Positive T-Lymphocytes; Diterpenes; DNA, Viral; Enzyme Activators; Female; Histone Deacetylase Inhibitors; HIV Infections; HIV-1; Humans; Hydroxamic Acids; Indoles; Male; Middle Aged; Panobinostat; Primary Cell Culture; Protein Kinase C; Viral Load; Virus Activation; Virus Latency