PROJECT SUMMARY ABSTRACT Increased comorbidities associated with aging such as atherosclerotic cardiovascular disease (CVD) is an emerging problem in HIV-1 infection despite potent antiretroviral therapy (ART). The SARS-CoV-2 pandemic emphasizes the urgent need to determine pathways that can be targeted by novel treatments. High-density lipoproteins (HDLs) are the most powerful negative predictors of CVD. Apolipoprotein A-I (apoA-I), the major protein of HDL, is responsible for the much of the anti-inflammatory properties of HDL. These effects can be mimicked by apoA-I peptides such as 4F that are promising therapy for CVD and have antiviral properties. Our goal is to examine whether statins have additive effects with apoA-I mimetics to attenuate key instigators of early vascular aging and lung tissue dysfunction in chronic treated HIV-1 infection and SARS-CoV-2 infection. In the setting of the main award, we will isolate monocytes (Aim 1), gut tissue explants (Aim 2) and endothelial cells (ECs) (Aim 3) from middle aged(MA)/older (O) (40-70 years old) HIV-infected ART-treated patients with suppressed viremia and subclinical CVD who receive (Group A) or not (Group B) statins. We will determine self-amplifying molecular pathways that involve the crosstalk between bioactive lipids, macrophages, epithelial and EC isolated from group A versus group B. In sub-aim 2 of each Aim we will expose (or not) in vitro blood monocytes, enterocytes, gut M/M, gut and whole blood ECs to physiologically relevant 4F concentrations in the setting of ex vivo assays of proatherogenic cellular dysfunction. In each aim, we will also include blocking ex vivo experiments and an exploratory approach to elucidate novel mechanisms of HIV-1 related CVD. In the setting of the Supplement award, in Aim 1 of this proposal and using an air-liquid interface (ALI) culture of primary airway epithelial cells, and cell lines in combination with viral and immune assays, we will determine the mechanisms how the combination of 4F with atorvastatin attenuates aberrant activation of proinflammatory pathways as a novel mechanism that drives viral replication and associated inflammatory responses in SARS- CoV-2 infected lung cells. Given that vascular dysfunction is a possible mechanism of chronic post-infectious sequalae of COVID-19, in Aim 2 of this proposal and using an established ex vivo model of vascular dysfunction and immune cells from COVID-19 patients, we will determine whether 4F and atorvastatin attenuate aberrant activation of the proinflammatory pathway in macrophages from COVID-19 patients that interact ex vivo with endothelial cells to drive proinflammatory proatherogenic responses. Our independent aims will complement each other and will advance the use of the combination of apoA-I mimetic peptides and statins as novel therapy for HIV and COVID-19. This work is innovative, interdisciplinary, public health-oriented, and directly addresses the goals of this funding opportunity.