Cocaine augments neuro-inflammation via modulating extracellular vesicle release in HIV-1 infected immune cells

Autoantibody-mediated disorders of the central and peripheral nervous system: Overview Infection

HIV-associated neurocognitive disorders are a common manifestation of HIV infection, affecting more than half of HIV-infected individuals, including those receiving targeted antiviral therapy. A common feature of the course of HIV infection during therapy is large-scale immune responses in the brain. Several pathways are involved in the neuropathogenesis of HIV infection: Cellular entry, inflammatory processes in microglia, activation of astroglia, myeloid cells, and damage to brain vessels leading to neurocirculatory disorders. Data on vascular diseases that influence the development of neurocognitive impairment in HIV-positive patients will also be examined, as well as better intervention strategies for complex neurocognitive disorders and neurodegenerative processes in HIV infection.

Single-cell sequencing reveals the heterogeneity of immune landscape in drug users with HIV infection

BACKGROUND

Injection drug use (IDU) leads to immune system dysfunction, thereby increasing the risk of opportunistic infection. There is a critical need to reveal the role of IDU in the immunopathogenesis of HIV infection.

METHODS

We performed single-cell RNA sequencing (scRNA-seq) on peripheral blood mononuclear cells (PBMCs) derived from healthy control (HC) individuals, HIV-infected patients with IDU (HIV-IDU) and without IDU (HIV-nIDU). In addition, the Gene Set Enrichment Analysis (GSEA) was used to analyze the immunomodulatory effects of differential immune cells.

RESULTS

Seven types of cells were identified with specific expressions of maker genes. Specific subsets such as CD14+ monocytes, plasmacytoid dendritic cells (pDCs), plasma cells, and CD8+ T cells displayed a high degree of heterogeneity among HC, HIV-nIDU, and HIV-IDU. We identified signature genes for each subset in distinct groups, including CFP+ CD14+ monocytes, PTPRCAP+ pDCs, IGHD+ plasma cells, and IFITM1+ CD8+T cells from HIV-IDU, whereas these genes were not expressed in such cells from HIV-nIDU. Moreover, considerable heterogeneity in the function of these immune cells was observed across different groups, especially the elevated IFN-α/β signaling for CD14+ monocytes, histone H2A/2B and H3/4 pathway for pDCs, the creation of C4 and C2 activators for plasma cells, and drug metabolism cytochrome p450 for CD8+ T cells in HIV-IDU individuals.

CONCLUSION

Our comprehensive analyses clarify the heterogeneous characteristics of the immune landscape between HIV-IDU and HIV-nIDU. These insights provide a deeper understanding of the IDU-mediated immunopathogenesis in HIV infection.

Analysis of Sigma-1 Receptor Antagonist BD1047 Effect on Upregulating Proteins in HIV-1-Infected Macrophages Exposed to Cocaine Using Quantitative Proteomics

HIV-1 infects monocyte-derived macrophages (MDM) that migrate into the brain and secrete virus and neurotoxic molecules, including cathepsin B (CATB), causing cognitive dysfunction. Cocaine potentiates CATB secretion and neurotoxicity in HIV-infected MDM. Pretreatment with BD1047, a sigma-1 receptor antagonist, before cocaine exposure reduces HIV-1, CATB secretion, and neuronal apoptosis. We aimed to elucidate the intracellular pathways modulated by BD1047 in HIV-infected MDM exposed to cocaine. We hypothesized that the Sig1R antagonist BD1047, prior to cocaine, significantly deregulates proteins and pathways involved in HIV-1 replication and CATB secretion that lead to neurotoxicity. MDM culture lysates from HIV-1-infected women treated with BD1047 before cocaine were compared with untreated controls using TMT quantitative proteomics, bioinformatics, Lima statistics, and pathway analyses. Results demonstrate that pretreatment with BD1047 before cocaine dysregulated eighty (80) proteins when compared with the infected cocaine group. We found fifteen (15) proteins related to HIV-1 infection, CATB, and mitochondrial function. Upregulated proteins were related to oxidative phosphorylation (SLC25A-31), mitochondria (ATP5PD), ion transport (VDAC2-3), endoplasmic reticulum transport (PHB, TMED10, CANX), and cytoskeleton remodeling (TUB1A-C, ANXA1). BD1047 treatment protects HIV-1-infected MDM exposed to cocaine by upregulating proteins that reduce mitochondrial damage, ER transport, and exocytosis associated with CATB-induced neurotoxicity.

The interplay among HIV, monocytes/macrophages, and extracellular vesicles: a systematic review

Despite effective antiretroviral therapies, chronic inflammation and spontaneous viral "blips" occur in HIV-infected patients. Given the roles for monocytes/macrophages in HIV pathogenesis and extracellular vesicles in intercellular communication, we performed this systematic review to delineate the triad of HIV, monocytes/macrophages, and extracellular vesicles in the modulation of immune activation and HIV activities. We searched PubMed, Web of Science, and EBSCO databases for published articles, up to 18 August 2022, relevant to this triad. The search identified 11,836 publications, and 36 studies were deemed eligible and included in this systematic review. Data were extracted for the characteristics of HIV, monocytes/macrophages, and extracellular vesicles used for experiments and the immunologic and virologic outcomes in extracellular vesicle recipient cells. Evidence for the effects on outcomes was synthesized by stratifying the characteristics by outcomes. In this triad, monocytes/macrophages were potential producers and recipients of extracellular vesicles, whose cargo repertoires and functionalities were regulated by HIV infection and cellular stimulation. Extracellular vesicles derived from HIV-infected monocytes/macrophages or the biofluid of HIV-infected patients enhanced innate immune activation and HIV dissemination, cellular entry, replication, and latency reactivation in bystander or infected target cells. These extracellular vesicles could be synthesized in the presence of antiretroviral agents and elicit pathogenic effects in a wide range of nontarget cells. At least eight functional types of extracellular vesicles could be classified based on the diverse extracellular vesicle effects, which were linked to specific virus- and/or host-derived cargos. Thus, the monocyte/macrophage-centered multidirectional crosstalk through extracellular vesicles may help sustain persistent immune activation and residual viral activities during suppressed HIV infection.

Role of macrophages in HIV pathogenesis and cure: NIH perspectives

Macrophages play a significant role in HIV infection and contribute to pathogenesis of comorbidities as well as establishment of the viral reservoir in people living with HIV. While CD4+ T cells are considered the main targets of HIV infection, infected macrophages resist the cytopathic effects of infection, contributing to the persistent HIV reservoir. Furthermore, activated macrophages drive inflammation and contribute to the development of comorbidities, including HIV-associated CNS dysfunction. Better understanding the role of macrophages in HIV infection, persistence, and comorbidities can lead to development of innovative therapeutic strategies to address HIV-related outcomes in people living with HIV. In October 2021, the National Institute of Mental Health and the Ragon Institute of MGH, MIT, and Harvard conducted a virtual meeting on role of macrophages in HIV infection, pathogenesis, and cure. This review article captures the key highlights from this meeting and provides an overview of interests and activities of various NIH institutes involved in supporting research on macrophages and HIV.