(W1294) EXPLORING AN ANTIRETROVIRAL DRUG DELIVERY RESEARCH TOOL USING HIV-INFECTED BLOOD BRAIN BARRIER COMPONENTS DERIVED FROM HUMAN INDUCED PLURIPOTENT STEM CELLS
Director BrainXell Madison, Wisconsin, United States
Abstract: The central nervous system (CNS) is one of the primary anatomic reservoirs for HIV latency, where virus can escape from antiretroviral therapy (ART) due to the presence of a blood-brain barrier (BBB), which restricts ART drugs from crossing the barrier and reaching the brain. Residual viral presence in the CNS can cause chronic inflammation and results in HIV-associated neurocognitive disorder (HAND). Obtaining functional human brain vasculature and tissue from healthy donors is nearly impossible, and post-mortem tissue from HIV patients poses a high infectious risk. Humanized animal models engrafted with human cells struggle to fully replicate human brain counterparts. For these reasons, precise recapitulation of the human BBB in vitro is critical to accelerating new ART drug discovery pipelines and treating the CNS-HIV infection. We acknowledge the urgent need for accurate human BBB models based on tissue-relevant, highly-enriched, brain microvascular endothelial cells (BMECs), pericytes, astrocytes, and microglia of consistent quality in order to dissect the mechanisms of cellular reservoirs of HIV in the CNS and to build high-throughput screening (HTS) platforms. To address these challenges, we differentiated hiPSC to generate highly enriched human BBB components including brain microvascular endothelial cells (BMEC) and pericytes, astrocytes and microglia, respectively. For HIV infection, we engineered GFP-pseudo HIV-1 packaged with a lentiviral GFP reporter and packaging plasmids. In the infectivity test, no significant morphological changes observed. Each BBB components showed high susceptibility to pseudoHIV; BMEC, pericyes, and astrocytes. However, microglia and glutamatergic neurons showed variable and low infectivity. Next, we tested Dolutegravir (DTG), a commercially available antiretroviral therapy (ART) drug, on HIV-infected cells. DTG was highly effective, reducing the viral load by 50% in EPCs, but it was not effective on pericytes and astrocytes. In the present study, we demonstrated the scalable generation of highly enriched hiPSC-derived BBB components and their susceptibility to pseudo-HIV. With enhanced HIV infectivity in microglia, we will mimic HIV infected BBB models in 2D and 3D formats, advancing the development of a comprehensive tool for HIV drug discovery.
