Emma Andraka*1, Megan McGraw*1, Skye Opsteen1, Lynn Prichard2, Kevin R. Robertson3, Babafemi Tiwo4, E. Turner Overton2, Gary R. Cutter5, Sonya Heath2, John J. Shacka1

*These authors contributed equally to this work

1Dept. of Pharmacology & Toxicology, University of Alabama at Birmingham, Birmingham, AL

2Dept. of Medicine, Division of Infectious Diseases, University of Alabama at Birmingham, Birmingham, AL

3Dept. of Neurology, University of North Carolina, Chapel Hill, NC

4Feinberg School of Medicine, Northwestern University, Chicago, IL

5Dept. of Biostatistics, University of Alabama at Birmingham, Birmingham, AL

Abstract:

Due to the success of antiretroviral therapy (ART), people living with HIV (PLWH) now exhibit near-normal life expectancies. However, a large percentage of PLWH still suffer from several comorbidities including HIV-associated neurocognitive disorders (HAND). Previous studies have determined the autophagy-lysosomal pathway (ALP) is dysregulated in peripheral blood mononuclear cells (PBMC) from PLWH. The relative function of the ALP can be assessed by measuring autophagic flux, by quantifying the accumulation of autophagosomes in the presence or absence of lysosome inhibition. However, prior studies have not evaluated autophagic flux in specific populations of PBMCs, nor evaluated the impact of HAND or ART. This ongoing study will test our hypotheses that autophagic flux is compromised in PLWH and is further compromised as a function of HAND. We predict ART will enhance autophagic flux in CD8-positive T-cells and CD14-positive monocytes, and that this enhancement may be compromised in PLWH identified with HAND. PBMCs were obtained from the following cohorts of participants in the ACTG-5303 study: PLWH without cognitive decline before (HN0) and after 48 weeks of tenofovir ART (HN48), and PLWH with mild-moderate cognitive decline before (HD0) and after ART (HD48). CD8-positive T-cells and CD14-positive monocytes were purified from PBMCs and then incubated in the presence or absence of chloroquine (CQ; 30 µM), a weak base that inhibits lysosome function, and in turn autophagic flux. Western blot analysis of cell lysates is ongoing to assess levels of LC3-II, a selective marker of autophagosomes, and P62, an ALP substrate. Levels of LC3-II and P62 in CD8-positive T-cells and CD14-positive monocytes from PLWH will also be compared to those obtained from healthy control participants. Completing this study will delineate the utility of autophagic flux in PBMCs for monitoring cognitive decline and response to ART in PLWH.