Monocyte-derived macrophages contain persistent latent HIV reservoirs

The development of persistent cellular reservoirs of latent human immunodeficiency virus (HIV) is a critical obstacle to viral eradication since viral rebound takes place once anti-retroviral therapy (ART) is interrupted. Previous studies show that HIV persists in myeloid cells (monocytes and macrophages) in blood and tissues in virologically suppressed people with HIV (vsPWH). However, how myeloid cells contribute to the size of the HIV reservoir and what impact they have on rebound after treatment interruption remain unclear. Here we report the development of a human monocyte-derived macrophage quantitative viral outgrowth assay (MDM-QVOA) and highly sensitive T cell detection assays to confirm purity. We assess the frequency of latent HIV in monocytes using this assay in a longitudinal cohort of vsPWH (n = 10, 100% male, ART duration 5-14 yr) and find half of the participants showed latent HIV in monocytes. In some participants, these reservoirs could be detected over several years. Additionally, we assessed HIV genomes in monocytes from 30 vsPWH (27% male, ART duration 5-22 yr) utilizing a myeloid-adapted intact proviral DNA assay (IPDA) and demonstrate that intact genomes were present in 40% of the participants and higher total HIV DNA correlated with reactivatable latent reservoirs. The virus produced in the MDM-QVOA was capable of infecting bystander cells resulting in viral spread. These findings provide further evidence that myeloid cells meet the definition of a clinically relevant HIV reservoir and emphasize that myeloid reservoirs should be included in efforts towards an HIV cure.

Intact HIV Reservoir in Monocytes Is Associated With Cognitive Function in Virally Suppressed Women With HIV

BACKGROUND

Monocytes are susceptible to human immunodeficiency virus (HIV) infection, form HIV reservoirs, and contribute to central nervous system complications (eg, cognitive impairment) in virally suppressed women with HIV (vsWWH). However, it remains unknown if the quality and/or quantity of the monocyte reservoir contributes to cognition in vsWWH.

METHODS

Sixty-two vsWWH (mean age = 56.1 years, SD = 7.1; 93% Black, non-Hispanic; all HIV RNA <250 copies/mL) completed a cognitive test battery, blood draw, and whole-blood immunophenotyping. Monocytes and CD4 T cells were isolated from a subset of 53 participants and the HIV reservoir was assessed using cell-specific intact proviral DNA assays (IPDA). Demographically adjusted z-scores were calculated for each outcome using data from participants without HIV in the Women's Interagency HIV Study. Cognitive outcomes of interest included domain-specific and global z-scores.

RESULTS

Thirty-Eight percent of vsWWH had detectable intact HIV genomes in monocytes (median = 21.5 copies/million). Higher levels of intact HIV genomes per million monocytes were associated with poorer verbal memory (delayed recall, r = 0.55, P = .01; recognition, r = 0.46, P = .04), fine motor skills (r = 0.50, P = .03), and global function (r = 0.47, P = .04). Higher levels of intact HIV genomes in monocytes were associated with percent intermediate monocytes (r = 0.60, P = .008), and the ratio of intact per intermediate monocyte was associated with worse memory (r = -0.59, P = .008). There were no associations between CD4 reservoir and cognition.

CONCLUSIONS

The number of intact HIV genomes per million monocytes was related to poorer cognition and the percentage of intermediate monocytes. These findings suggest that the presence of HIV genomes in general do not relate to cognitive complications, but intact, and therefore potentially replication-competent HIV, may contribute to cognitive complications in vsWWH.