Mechanisms of atherosclerotic cardiovascular complications in COVID19

PROJECT SUMMARY The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), remains a global health concern and despite the fast-track development of vaccines and the imminent prospective of new antiviral drugs, is expected to become endemic. COVID-19 is associated with atherosclerotic cardiovascular (CV) complications like acute coronary syndrome (ACS), Myocardial Infarction (MI) and stroke, a risk that remains high for up to one year following recovery, but the underlying mechanisms are poorly understood. In preliminary work using atherosclerotic tissue from COVID-19 patients at autopsy and subjects who recovered from COVID-19, along with an ex-vivo SARS-CoV-2 model of human vascular explants, we identified SARS-CoV-2 viral material in human plaques that persists in plaques of patients who recovered from COVID-19. Single cell RNA sequencing (scRNAseq) of human atherosclerotic plaques identified high levels of neuropilin-1 (NRP1), a receptor for SARS-CoV-2 entry, in plaque macrophages and foam cells. NRP-1 blockade abrogated the accumulation of viral material in SARS-CoV-2 treated human plaques. These data suggest that SARS-COV-2 or its viral components can accumulate in human plaques, where they exacerbate inflammation and disease progression by engaging NRP-1. Using the Syrian Golden hamster model, that faithfully mimics human SARS-CoV2 infection, we found that viral replication in the heart, lungs and olfactory bulb of infected hamsters did not correlate with expression levels of Ace2, supporting a role for alternative mechanisms of viral entry such as NRP-1. Moreover, this model revealed acute and sustained tissue-specific inflammatory responses (i.e. Nfkb1, Il6, Il1b) in several tissues due to the persistence in the circulation of noninfectious viral RNA debris (vRNA) for up to several weeks following viral clearance. Based on these exciting preliminary data, we propose two independent aims to study how SARS-CoV-2 aggravates plaque inflammation and atherosclerosis and to determine the molecular basis for the increased risk of acute and long-term CV events in COVID-19 patients. In Aim 1 we will identify the role of NRP-1 in SARS-CoV-2-induced atherosclerotic plaque inflammation and atherosclerosis progression. Aim 2 will identify the contribution of SARS-CoV-2 vRNA debris to inflammation and atherosclerosis. We will also determine the effect of persistent vRNA on inflammation and atherogenesis following viral clearance and recovery from COVID-19. These studies will address important gaps in knowledge on the effect of SARS-CoV-2 infection on plaque inflammation and atherosclerosis, and will tackle the molecular basis for the increased CV in patients with COVID-19. We foresee that this information will help guide the future design of precise therapies to prevent CV outcomes in patients with COVID-19.