HIV-1DetectionandEliminationFrom CNS Mononuclear Phagocytes - ABSTRACT Mononuclear phagocytes (MP; monocytes, macrophages, dendritic cells. and microglia) serve as human immunodeficiency virus type one (HIV-1) reservoirs, sites of viral persistence and latency, and inducers of end- organ disease. All are commonly linked to HIV-1 pathobiology. However, the key relevance of the MP viral reservoir rests in the central nervous system (CNS) of those people living with HIV (PLWH). In those PLWH and receiving antiretroviral therapy (ART), the evidence for the size, scope, and disease relevance of the CNS viral reservoir remains under appreciated. The discordance between laboratory MP infection and tissue persistence in an infected human host is also not yet known. MP can have an extended life span and possess self-renewing potential, and as such, are likely more relevant in disease than currently appreciated. Evaluation of the significance of MPs, in general, and the microglia specifically will help define the importance of MPs during natural infection. For the CNS specifically, HIV-1 enters the brain soon after infection and replicates in perivascular macrophages and MGL along with limited numbers of astrocytes. Viral set point and timing of ART initiation determines the latent reservoir size; each affects the efficiency of any eradication strategy. Knowledge of the viral dynamics, CNS viral invasion, susceptibility to MP infection, and composition of CNS HIV reservoir will facilitate effective therapeutic interventions. To each of these ends, we will employ novel techniques to study the MP HIV-1 reservoir in laboratory systems and in a newly developed human microglial mouse model of human disease. We will use basic and applied MP biology, theranostics, novel ART nanoformulations, molecular and cellular biology, and our unique animal model to study the means to eliminate viral infection at the subcellular, cellular, and tissue level with newly designed and novel therapeutic methods that include gene therapy strategies. Our aims are to determine the efficiency of viral suppression by native and nanoformulated ART (at subcellular level), assess the breadth of the CNS viral reservoirs against viral set points (defined by the initiation of ART), and to explore combination strategies for HIV-1 elimination in a new developed humanized microglial mouse.