Cocaethylene, simultaneous alcohol and cocaine use, and liver fibrosis in people living with and without HIV

BACKGROUND: The simultaneous consumption of cocaine and alcohol results in the production of cocaethylene (CE) in the liver, a highly toxic metabolite. Prior research suggests that cocaine use contributes to liver disease and its concomitant use with alcohol may increase its hepatotoxicity, but studies in humans are lacking. We evaluated the role of cocaine, its simultaneous use with alcohol, and CE on liver fibrosis. METHODS: We performed a cross-sectional analysis of the Miami Adult Studies on HIV (MASH) cohort. Cocaine use was determined via self-report, urine screen, and blood metabolites, using liquid chromatography with tandem mass spectrometry. Hazardous drinking was determined with the AUDIT-C and liver fibrosis with the Fibrosis-4 Index (FIB-4). RESULTS: Out of 649 participants included in this analysis, 281 (43.3%) used cocaine; of those, 78 (27.8%) had CE in blood. Cocaine users with CE had higher concentrations of cocaine metabolites in blood and were more likely to drink hazardously than cocaine users without CE and cocaine non-users. Overall, cocaine use was associated with liver fibrosis. CE in blood was associated with 3.17 (95% CI: 1.61, 6.23; p = 0.0008) times the odds of liver fibrosis compared to cocaine non-users, adjusting for covariates including HIV and HCV infection. The effect of CE on liver fibrosis was significantly greater than that of cocaine or alcohol alone. CONCLUSIONS: CE is a reliable marker of simultaneous use of cocaine and alcohol that may help identify individuals at risk of liver disease and aid in the prevention of its development or progression

HIV Infection Rapidly Induces and Maintains a Substantial Suppression of Thymocyte Proliferation

International audienceThe supply of naive T cells by the thymus normally requires precursor T cell proliferation within the thymus and would be particularly important in the setting of HIV infection when both naive and memory T cells are progressively depleted. As a robust, quantitative index of intrathymic proliferation, the ratio of different T cell receptor excision circles (TRECs), molecular markers of distinct T cell receptor rearrangements occurring at different stages of thymocyte development, was measured in peripheral blood-mononuclear cells (PBMCs). This ratio has the virtue that it is a "signature" of thymic emigrants throughout their entire life and, thus, can be measured in peripheral cell populations that are easy to obtain. Using the new assay, we evaluated the effect of HIV infection on intrathymic precursor T cell proliferation by longitudinal analysis of PBMCs from recently infected individuals. Our findings reveal a substantial reduction in intrathymic proliferation. The analysis also indicates the existence of a compensatory mechanism acting to sustain the numbers of recent thymic emigrants (RTEs) in the periphery

Cocaine use associated gut permeability and microbial translocation in people living with HIV in the Miami Adult Study on HIV (MASH) cohort

OBJECTIVE: Determine if cocaine use impacts gut permeability, promotes microbial translocation and immune activation in people living with HIV (PLWH) using effective antiretroviral therapy (ART). METHODS: Cross-sectional analysis of 100 PLWH (ART ≥6 months, HIV-RNA \u3c200 copies/mL) from the Miami Adult Studies on HIV (MASH) cohort. Cocaine use was assessed by self-report, urine screen, and blood benzoylecgonine (BE). Blood samples were collected to assess gut permeability (intestinal fatty acid-binding protein, I-FABP), microbial translocation (lipopolysaccharide, LPS), immune activation (sCD14, sCD27, and sCD163) and markers of inflammation (hs-CRP, TNF-α and IL-6). Multiple linear regression models were used to analyze the relationships of cocaine use. RESULTS: A total of 37 cocaine users and 63 cocaine non-users were evaluated. Cocaine users had higher levels of I-FABP (7.92±0.35 vs. 7.69±0.56 pg/mL, P = 0.029) and LPS (0.76±0.24 vs. 0.54±0.27 EU/mL, P\u3c0.001) than cocaine non-users. Cocaine use was also associated with the levels of LPS (P\u3c0.001), I-FABP (P = 0.033), and sCD163 (P = 0.010) after adjusting for covariates. Cocaine users had 5.15 times higher odds to exhibit higher LPS levels than non-users (OR: 5.15 95% CI: 1.89-13.9; P\u3c0.001). Blood levels of BE were directly correlated with LPS (rho = 0.276, P = 0.028), sCD14 (rho = 0.274, P = 0.031), and sCD163 (rho = 0.250, P = 0.049). CONCLUSIONS: Cocaine use was associated with markers of gut permeability, microbial translocation, and immune activation in virally suppressed PLWH. Mitigation of cocaine use may prevent further gastrointestinal damage and immune activation in PLWH

Nef promotes evasion of human immunodeficiency virus type 1-infected cells from the CTLA-4-mediated inhibition of T-cell activation.

International audienceCTLA-4 is a negative regulator of T-cell receptor-mediated CD4(+) T-cell activation and function. Upregulation of CTLA-4 during human immunodeficiency virus type 1 (HIV-1) infection on activated T cells, particularly on HIV-specific CD4(+) T cells, correlates with immune dysfunction and disease progression. As HIV-1 infects and replicates in activated CD4(+) T cells, we investigated mechanisms by which HIV-1 modulates CTLA-4 expression to establish productive viral infection in these cells. Here, we demonstrate that HIV-1 infection in activated CD4(+) T cells was followed by Nef-mediated downregulation of CTLA-4. This was associated with a decreased T-cell activation threshold and significant resistance to CTLA-4 triggering. In line with these in vitro results, quantification of pro-viral HIV DNA from treatment-naive HIV-infected subjects demonstrated a preferential infection of memory CD4(+)CTLA-4(+) T cells, thus identifying CTLA-4 as a biomarker for HIV-infected cells in vivo. As transcriptionally active HIV-1 and Nef expression in vivo were previously shown to take place mainly in the CD3(+)CD4(-)CD8(-) [double-negative (DN)] cells, we further quantified HIV DNA in the CTLA-4(+) and CTLA-4(-) subpopulations of these cells. Our results showed that DN T cells lacking CTLA-4 expression were enriched in HIV DNA compared with DN CTLA-4(+) cells. Together, these results suggested that HIV-1 preferential infection of CD4(+)CTLA-4(+) T cells in vivo was followed by Nef-mediated concomitant downregulation of both CD4 and CTLA-4 upon transition to productive infection. This also highlights the propensity of HIV-1 to evade restriction of the key negative immune regulator CTLA-4 on cell activation and viral replication, and therefore contributes to the overall HIV-1 pathogenesis

CD160 and PD-1 Co-Expression on HIV-Specific CD8 T Cells Defines a Subset with Advanced Dysfunction

<div><p>Chronic viral infections lead to persistent CD8 T cell activation and functional exhaustion. Expression of programmed cell death-1 (PD-1) has been associated to CD8 T cell dysfunction in HIV infection. Herein we report that another negative regulator of T cell activation, CD160, was also upregulated on HIV-specific CD8 T lymphocytes mostly during the chronic phase of infection. CD8 T cells that expressed CD160 or PD-1 were still functional whereas co-expression of CD160 and PD-1 on CD8 T cells defined a novel subset with all the characteristics of functionally exhausted T cells. Blocking the interaction of CD160 with HVEM, its natural ligand, increased HIV-specific CD8 T cell proliferation and cytokine production. Transcriptional profiling showed that CD160⁻PD-1⁺CD8 T cells encompassed a subset of CD8⁺ T cells with activated transcriptional programs, while CD160⁺PD-1⁺ T cells encompassed primarily CD8⁺ T cells with an exhausted phenotype. The transcriptional profile of CD160⁺PD-1⁺ T cells showed the downregulation of the NFκB transcriptional node and the upregulation of several inhibitors of T cell survival and function. Overall, we show that CD160 and PD-1 expressing subsets allow differentiating between activated and exhausted CD8 T cells further reinforcing the notion that restoration of function will require multipronged approaches that target several negative regulators.</p> </div

Summary of clinical characteristics.

<p>Summary of clinical characteristics.</p

Co-expression of CD160 and PD-1 identifies a fully exhausted antigen-specific CD8 T cell.

<p>PBMCs were isolated from HIV viremic individuals (n = 14) and stimulated with (A) SEB, (B) CMV and (C) HIV-1 peptides and analyzed by multiparametric flow cytometry for CD160, PD-1, IFNγ, TNFα and CD107a expression. HIV and CMV-specific CD8 T cells were identified using PE-conjugated tetramers. Dying cells were eliminated with an amine-reactive viability dye. # symbols represent statistically significant comparisons with the DP subset. <i>P</i>-values were determined by the Wilcoxon matched pairs test. ##represents a <i>P</i> value<0.005 and # represents a <i>P</i> value<0.05.</p

CD160⁺PD-1⁺CD8 T cells represent a distinct subset with a unique transcriptional profile.

<p>PBMCs were stained with 7AAD (cell viability dye), αCD3, αCD8, αPD-1, αCD160 and total CD8 T cells were sorted using a FACS ARIA based on CD160 and PD-1 expression. (A) Heatmap illustrating the differentially expressed genes (39 genes; p<0.05) between DP and SP-PD-1 sorted subsets. (B) Network analysis of significantly inferred genes and predicted targets. Node colors indicate fold change of gene expression between ex-vivo sorted CD160⁺PD-1⁺ and CD160⁻PD-1⁺ CD8 T cells sorted from 4 HIV viremic patients. The different shapes indicate genes in the different functional categories (see legend). (C) Histogram and scatter plot showing the MFI of KIR2DL2 and KIR2DL3 expression on DP and SP-PD-1 subsets in 6 HIV viremic patients.</p