Mechanistic Studies of Gut Dysfunction Exacerbation due to SARS-CoV-2 in HIV/SIV infected Individuals

Abstract With more than 60 million SARS-CoV-2 -infected patients worldwide and nearly 1.5 million COVID-19-related deaths recoreded thus far (November 25), the COVID pandemic is one of the most critical global health problem ever known to humankind, and a major emergency in the US. COVID-19 disproportionately impacts elders or subjects with pre-existing conditions. Considering that the majority of persons living with HIV and AIDS (PLWHA) in the US are aged over 50 years and that even the younger PLWHA present with accelerated aging and multiple comorbidities related to HIV-induced excessive chronic inflammation, it is expected that COVID-19 will be particularly severe in this risk group. Similar to HIV, SARS-CoV-2 replicates in the gut, and patients with gastrointestinal symptoms were reported to have a more severe outcome. The exact mechanism through which SARS-CoV-2 impacts the gut health remains elusive, however it is very likely that the two viruses can potentiate each other through exacerbation of the gut lesions. Here, we will test the hypothesis that exacerbation of the gut dysfunction of the SIV-infected PTMs after SARS-CoV-2 superinfection occurs through triggering excessive mobilization, activation and NETosis of neutrophils at mucosal site and consequent gut collateral damages. Such a scenario will result not only in an increased risk of the PLWHA to develop more severe forms of COVID-19, but also to a significant boost of HIV pathogenicity through (i) losing control of HIV at mucosal sites; (ii) depletion of mucosal and systemic immune effectors; (iii) increases of mucosal and systemic levels of inflammation; and (iv) enhancement of pre-existent SIV-related comorbidities. This innovative project is designed to assess pathogenic pathways impacted by SARS-CoV-2 in the gut, to understand the natural history of COVID-19 related to either triggering or exacerbating HIV-associated gut dysfunction and comorbidities. We will identify risk factors that could prompt therapy changes in high-risk individuals, such as the PLWH. Our highly translational project addresses key scientific questions identified as critical by the NIDDK, thus being highly responsive to RFA 20-021.