Defining the Effects of PKC Modulator HIV Latency-Reversing Agents on Natural Killer Cells

Melanie Dimapasoc; Jose A Moran; Steve W Cole; Alok Ranjan; Rami Hourani; Jocelyn T Kim; Paul A Wender; Matthew D Marsden; Jerome A Zack

doi:10.20411/pai.v9i1.673

Defining the Effects of PKC Modulator HIV Latency-Reversing Agents on Natural Killer Cells

Pathog Immun. 2024 Apr 24;9(1):108-137. doi: 10.20411/pai.v9i1.673. eCollection 2024.

Authors

Melanie Dimapasoc^{1

2}, Jose A Moran³, Steve W Cole⁴, Alok Ranjan⁵, Rami Hourani⁵, Jocelyn T Kim⁶, Paul A Wender^{5

7}, Matthew D Marsden^{3

8}, Jerome A Zack^{2

9}

Affiliations

¹ Molecular Biology Institute, University of California Los Angeles, Los Angeles, California.
² Department of Microbiology, Immunology, and Molecular Genetics, University of California Los Angeles, Los Angeles, California.
³ Department of Microbiology and Molecular Genetics, School of Medicine, University of California Irvine, California.
⁴ UCLA Department of Psychiatry & Biobehavioral Sciences, David Geffen School of Medicine at UCLA, Los Angeles, California.
⁵ Department of Chemistry, Stanford University, Stanford, California.
⁶ Department of Medicine, Division of Infectious Diseases, University of California Los Angeles, Los Angeles, California.
⁷ Department of Chemical and Systems Biology, Stanford University, Stanford, California.
⁸ Department of Medicine, Division of Infectious Diseases, School of Medicine, University of California, Irvine, Irvine, California.
⁹ Department of Medicine, Division of Hematology and Oncology, University of California Los Angeles, Los Angeles, California.

Abstract

Background: Latency reversing agents (LRAs) such as protein kinase C (PKC) modulators can reduce rebound-competent HIV reservoirs in small animal models. Furthermore, administration of natural killer (NK) cells following LRA treatment improves this reservoir reduction. It is currently unknown why the combination of a PKC modulator and NK cells is so potent and whether exposure to PKC modulators may augment NK cell function in some way.

Methods: Primary human NK cells were treated with PKC modulators (bryostatin-1, prostratin, or the designed, synthetic bryostatin-1 analog SUW133), and evaluated by examining expression of activation markers by flow cytometry, analyzing transcriptomic profiles by RNA sequencing, measuring cytotoxicity by co-culturing with K562 cells, assessing cytokine production by Luminex assay, and examining the ability of cytokines and secreted factors to independently reverse HIV latency by co-culturing with Jurkat-Latency (J-Lat) cells.

Results: PKC modulators increased expression of proteins involved in NK cell activation. Transcriptomic profiles from PKC-treated NK cells displayed signatures of cellular activation and enrichment of genes associated with the NFκB pathway. NK cell cytotoxicity was unaffected by prostratin but significantly decreased by bryostatin-1 and SUW133. Cytokines from PKC-stimulated NK cells did not induce latency reversal in J-Lat cell lines.

Conclusions: Although PKC modulators have some significant effects on NK cells, their contribution in "kick and kill" strategies is likely due to upregulating HIV expression in CD4⁺ T cells, not directly enhancing the effector functions of NK cells. This suggests that PKC modulators are primarily augmenting the "kick" rather than the "kill" arm of this HIV cure approach.

Keywords: Acquired Immunodeficiency Syndrome; HIV-1; Immunity; Killer Cells, Natural; Protein Kinase C; Virus Latency.