Introduction: For many therapeutic drugs, including antiretroviral drugs used to treat people living with HIV-1 (PLWH), we have little data on the potential effects on the developing human brain due to limited access to tissue and historical constraints on the inclusion of pregnant populations in clinical trials. Human induced pluripotent stem cells (iPSCs) offer a new avenue to gain insight on how drugs may impact human cell types representative of the developing central nervous system. To prevent vertical transmission of HIV and promote the health of pregnant PLWH, antiretroviral therapy must be initiated and/or maintained throughout pregnancy.
View Article and Find Full Text PDF"Despite ART, we detected occasional microglia containing cell-associated HIV RNA and HIV DNA integrated into open regions of the host's genome (∼0.005%)" should be corrected to: "Despite ART, we detected occasional microglia containing cell-associated HIV RNA and HIV DNA integrated into open regions of the host's genome (∼0.5%).
View Article and Find Full Text PDFCommon single-nucleotide variants (SNVs) of eukaryotic translation initiation factor 2 alpha kinase 3 (EIF2AK3) slightly increase the risk of disorders in the periphery and the central nervous system. EIF2AK3 encodes protein kinase RNA-like endoplasmic reticulum kinase (PERK), a key regulator of ER stress. Three exonic EIF2AK3 SNVs form the PERK-B haplotype, which is present in 28% of the global population.
View Article and Find Full Text PDFThe presence of HIV in sequestered reservoirs is a central impediment to a functional cure, allowing HIV to persist despite life-long antiretroviral therapy (ART), and driving a variety of comorbid conditions. Our understanding of the latent HIV reservoir in the central nervous system is incomplete, because of difficulties in accessing human central nervous system tissues. Microglia contribute to HIV reservoirs, but the molecular phenotype of HIV-infected microglia is poorly understood.
View Article and Find Full Text PDFBased on emerging evidence on the role for specific single-nucleotide variants (SNVs) in EIF2AK3 encoding the integrated stress response kinase PERK, in neurodegeneration, we assessed the association of EIF2AK3 SNVs with neurocognitive performance in people with HIV (PWH) using a candidate gene approach. This retrospective study included the CHARTER cohort participants, excluding those with severe neuropsychiatric comorbidities. Genome-wide data previously obtained for 1047 participants and targeted sequencing of 992 participants with available genomic DNA were utilized to interrogate the association of three noncoding and three coding EIF2AK3 SNVs with the continuous global deficit score (GDS) and global neurocognitive impairment (NCI; GDS ≥ 0.
View Article and Find Full Text PDFThe central nervous system encounters a number of challenges following HIV infection, leading to increased risk for a collection of neurocognitive symptoms clinically classified as HIV-associated neurocognitive disorders (HAND). Studies attempting to identify causal mechanisms and potential therapeutic interventions have historically relied on primary rodent neurons, but a number of recent reports take advantage of iPSC-derived neurons in order to study these mechanisms in a readily reproducible, human model. We found that iPSC-derived neurons differentiated via an inducible neurogenin-2 transcription factor were resistant to gross toxicity from a number of HIV-associated insults previously reported to be toxic in rodent models, including HIV-infected myeloid cell supernatants and the integrase inhibitor antiretroviral drug, elvitegravir.
View Article and Find Full Text PDFCombined antiretroviral therapy (cART) has greatly decreased mortality and morbidity among persons with HIV; however, neurologic impairments remain prevalent, in particular HIV-associated neurocognitive disorders (HANDs). White matter damage persists in cART-treated persons with HIV and may contribute to neurocognitive dysfunction as the lipid-rich myelin membrane of oligodendrocytes is essential for efficient nerve conduction. Because of the importance of lipids to proper myelination, we examined the regulation of lipid synthesis in oligodendrocyte cultures exposed to the integrase strand transfer inhibitor elvitegravir (EVG), which is administered to persons with HIV as part of their initial regimen.
View Article and Find Full Text PDFOligodendrocytes (OLs), the myelin-generating cells of the central nervous system (CNS), are active players in shaping neuronal circuitry and function. It has become increasingly apparent that injury to cells within the OL lineage plays a central role in neurodegeneration. In this review, we focus primarily on three degenerative disorders in which white matter loss is well documented: Alzheimer's disease (AD), Parkinson's disease (PD), and amyotrophic lateral sclerosis (ALS).
View Article and Find Full Text PDFAn enhanced understanding of neurotransmitter systems contributing to pain transmission aids in drug development, while the identification of biological variables like age and sex helps in the development of personalized pain management and effective clinical trial design. This study identified enhanced expression of purinergic signaling components specifically in painful inflammation, with levels increased more in women as compared to men. Inflammatory dental pain is common and potentially debilitating; as inflammation of the dental pulp can occur with or without pain, it provides a powerful model to examine distinct pain pathways in humans.
View Article and Find Full Text PDFBackground: Demographic diversity is not represented in the HIV/AIDS workforce. Engagement of underrepresented trainees as early as high school may address this disparity.
Methods: We established the Penn Center for AIDS Research (CFAR) Scholars Program, a mentored research experience for underrepresented minority (URM) trainees spanning educational stages from high school to medical school.
Background: The Centers for AIDS Research Diversity, Equity, and Inclusion Pathway Initiative (CDEIPI) aims to establish programs to develop pathways for successful careers in HIV science among scholars from underrepresented racial and ethnic populations. This article describes cross-site evaluation outcomes during the first 18 months (July 2021-December 2022) across 15 programs.
Methods: The aims of the evaluation were to characterize participants, describe feasibility, challenges, and successes of the programs and provide a basis for the generalizability of best practices to Diversity, Equity, and Inclusion (DEI) programs in the United States.
Background: There is an urgent need to increase diversity among scientific investigators in the HIV research field to be more reflective of communities highly affected by the HIV epidemic. Thus, it is critical to promote the inclusion and advancement of early-stage scholars from racial and ethnic groups underrepresented in HIV science and medicine.
Methods: To widen the HIV research career pathway for early-stage scholars from underrepresented minority groups, the National Institutes of Health supported the development of the Centers for AIDS Research (CFAR) Diversity, Equity, and Inclusion Pathway Initiative (CDEIPI).
White matter deficits are a common neuropathologic finding in neurologic disorders, including HIV-associated neurocognitive disorders (HAND). In HAND, the persistence of white matter alterations despite suppressive antiretroviral (ARV) therapy suggests that ARVs may be directly contributing to these impairments. Here, we report that a frontline ARV, bictegravir (BIC), significantly attenuates remyelination following cuprizone-mediated demyelination, a model that recapitulates acute demyelination, but has no impact on already formed mature myelin.
View Article and Find Full Text PDFCopper is an essential metal nutrient for life that often relies on redox cycling between Cu(I) and Cu(II) oxidation states to fulfill its physiological roles, but alterations in cellular redox status can lead to imbalances in copper homeostasis that contribute to cancer and other metalloplasias with metal-dependent disease vulnerabilities. Copper-responsive fluorescent probes offer powerful tools to study labile copper pools, but most of these reagents target Cu(I), with limited methods for monitoring Cu(II) owing to its potent fluorescence quenching properties. Here, we report an activity-based sensing strategy for turn-on, oxidation state-specific detection of Cu(II) through metal-directed acyl imidazole chemistry.
View Article and Find Full Text PDFNeurologic deficits associated with human immunodeficiency virus (HIV) infection impact about 50% of persons with HIV (PWH). These disorders, termed HIV-associated neurocognitive disorders (HAND), possess neuropathologic similarities to Alzheimer's disease (AD), including intra- and extracellular amyloid-beta (Aβ) peptide aggregates. Aβ peptide is produced through cleavage of the amyloid precursor protein (APP) by the beta secretase BACE1.
View Article and Find Full Text PDFIntroduction: Despite viral suppression due to combination antiretroviral therapy (cART), HIV-associated neurocognitive disorders (HAND) continue to affect half of people with HIV, suggesting that certain antiretrovirals (ARVs) may contribute to HAND.
Methods: We examined the effects of nucleoside/nucleotide reverse transcriptase inhibitors tenofovir disoproxil fumarate (TDF) and emtricitabine (FTC) and the integrase inhibitors dolutegravir (DTG) and elvitegravir (EVG) on viability, structure, and function of glutamatergic neurons (a subtype of CNS neuron involved in cognition) derived from human induced pluripotent stem cells (hiPSC-neurons), and primary human neural precursor cells (hNPCs), which are responsible for neurogenesis.
Results: Using automated digital microscopy and image analysis (high content analysis, HCA), we found that DTG, EVG, and TDF decreased hiPSC-neuron viability, neurites, and synapses after 7 days of treatment.
The persistence of human immunodeficiency virus-1 (HIV)-associated neurocognitive disorders (HAND) in the era of effective antiretroviral therapy suggests that modern HIV neuropathogenesis is driven, at least in part, by mechanisms distinct from the viral life cycle. Identifying more subtle mechanisms is complicated by frequent comorbidities in HIV populations. One of the common confounds is substance abuse, with cannabis being the most frequently used psychoactive substance among people living with HIV.
View Article and Find Full Text PDFDespite combined antiretroviral therapy (cART), HIV-associated neurocognitive disorder (HAND) affects 30-50% of HIV-positive patients. Importantly, persistent white matter pathologies, specifically corpus callosum thinning and disruption of white matter microstructures observed in patients with HAND despite viral control through cART, raise the possibility that HIV infection in the setting of suboptimal cART may perturb oligodendrocyte (OL) maturation, function and/or survival, influencing HAND persistence in the cART era. To examine the effect of HIV infection on OL maturation, we used supernatants of primary human monocyte-derived macrophages infected with HIV (HIV/MDMs) to treat primary cultures of rat oligodendrocyte precursor cells (OPCs) during their differentiation to mature OLs.
View Article and Find Full Text PDFJ Neuroimmune Pharmacol
March 2021
Persistence of cognitive, behavioral and, to a lesser extent, motor dysfunction in People living with HIV (PLWH) despite viral suppression has raised the question about the potential contribution of antiretroviral (ARV) compounds themselves. Converging clinical and experimental evidence support a contribution of ARV compounds. In this issue we explore the existing clinical evidence on the impact of antiretroviral therapy (ART) on the CNS across the age continuum and in women.
View Article and Find Full Text PDFThis protocol establishes a tri-culture of hiPSC-derived neurons, astrocytes, and microglia for the study of cellular interactions during homeostasis, injury, and disease. This system allows for mechanistic studies that can identify the roles of individual cell types in disease and injury response in a physiologically relevant, all-human system. This protocol utilizes and modifies prior differentiations.
View Article and Find Full Text PDFRegardless of adherence to combined antiretroviral therapy, white matter and myelin pathologies persist in patients with HIV-associated neurocognitive disorders, a spectrum of cognitive, motor, and behavioral impairments. We hypothesized that antiretroviral therapy alters the maturation of oligodendrocytes which synthesize myelin. We tested whether specific frontline integrase strand transfer inhibitors would alter oligodendrocyte differentiation and myelination.
View Article and Find Full Text PDFHIV-associated neurocognitive disorders (HAND) affect over half of HIV-infected individuals, despite antiretroviral therapy (ART). Therapeutically targetable mechanisms underlying HAND remain elusive, partly due to a lack of a representative model. We developed a human-induced pluripotent stem cell (hiPSC)-based model, independently differentiating hiPSCs into neurons, astrocytes, and microglia, and systematically combining to generate a tri-culture with or without HIV infection and ART.
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