ABSTRACT
The COVID-pandemic has contributed to more than 5 million deaths worldwide in the last two years. Co-morbid conditions such as Type 2 Diabetes (T2D) , HTN, obesity, and CKD have been associated with increased mortality with COVID-19. In a large meta-analysis, the relative risk of mortality was 1.54 for patients with T2D and COVID-19. Thus, there is an imperative need to develop a platform for rapid and reliable drug screening/selection against COVID-related morbidity/mortality in T2D patients. With limited translatability of in vitro and small animal models to humans, human organ-on-a-chip models are an attractive platform to model in vivo disease conditions and test potential therapeutics. We seeded T2D or nondiabetes patient-derived macrophage and human liver sinusoidal endothelial cells along with normal hepatocytes and kupffer cells in the liver-on-a-chip (LAMPS - Liver Acinus MicroPhysiological System) developed by our group, perfused with media mimicking normal fasting or late metabolic syndrome (LMS - high levels of glucose, fatty acids, insulin, glucagon) states. We transduced both macrophage and endothelial cells to overexpress the SARS-CoV2-S (spike) protein and compared it with a control lentivirus transduction. We found that T2D cells overexpressing S-protein in LMS media (T2D chip) displayed an increased secretion of inflammatory cytokines compared to the nondiabetes chip over days. We then tested the effect of Tocilizumab (IL6-receptor antagonist) in T2D chips. Compared to vehicle control, Tocilizumab significantly decreased the S-protein induced inflammatory cytokine secretion in T2D chips but not in nondiabetes chips, indicating its higher efficacy in severe disease states only. This is consistent with what was observed in large clinical trials providing confirmatory evidence that the LAMPS T2D and nondiabetes chips serve as a relevant in vitro model system to replicate human in vivo pathophysiology of COVID and for screening potential therapeutics.
ABSTRACT
Understanding the mechanism of SARS-CoV-2 infection and identifying potential therapeutics are global imperatives. Using a quantitative systems pharmacology approach, we identified a set of repurposable and investigational drugs as potential therapeutics against COVID-19. These were deduced from the gene expression signature of SARS-CoV-2-infected A549 cells screened against Connectivity Map and prioritized by network proximity analysis with respect to disease modules in the viral-host interactome. We also identified immuno-modulating compounds aiming at suppressing hyperinflammatory responses in severe COVID-19 patients, based on the transcriptome of ACE2-overexpressing A549 cells. Experiments with Vero-E6 cells infected by SARS-CoV-2, as well as independent syncytia formation assays for probing ACE2/SARS-CoV-2 spike protein-mediated cell fusion using HEK293T and Calu-3 cells, showed that several predicted compounds had inhibitory activities. Among them, salmeterol, rottlerin, and mTOR inhibitors exhibited antiviral activities in Vero-E6 cells; imipramine, linsitinib, hexylresorcinol, ezetimibe, and brompheniramine impaired viral entry. These novel findings provide new paths for broadening the repertoire of compounds pursued as therapeutics against COVID-19.