Summary:  

The study was to test the anti-SARS-CoV activity in a traditional Chinese medicine (TCM), RDS (Respiratory Detox Shot), using Virongy’s SARS-CoV S protein pseudotyped GFP or luciferase reporter lentiviruses. The target cells were Vero E6 and ACE2-expressing A549 cell  (human lung epithelia cell). Virongy performed experiments to test and quantify the anti-SARS-CoV activity of RDS, and found that RDS possesses anti-SARS-CoV activity. Mechanistic studies further demonstrated that RDS blocked SARS-CoV S protein-mediated viral entry into ACE2+ target cells. Dose-response curves, using RDS concentration at 1:10, 1:20, 1:40, 1:80, 1:160, 1:320, and 1:640 dilution, were plotted to determine RDS’ anti-viral potency. The IC50s (50% virus inhibition dosage) were determined to be at 1:160 dilution (Vero E6 cell) and 1:70.88 dilution [A549(ACE2) cells]. The LC50 (50% cytotoxicity) on A549(ACE2) cells was also determined to be at 1:11.89 dilution.

Introduction:

Respiratory Detox Shot (RDS) is a mixture of traditional Chinese medicine that has been used in China for the management of lung function and SARS-CoV and –CoV-2 infection. We preformed experiments to determine whether RDS has anti-coronavirus activity and quantified its antiviral potency. For the experiments, RDS was serially diluted, and then used to treat Vero E6 or A549(ACE2) target cells to block SARS-CoV pseudovirus infection. Inhibition of viral transduction and viral entry were analyzed for reporter GFP (green fluorescent protein) or Luc (luciferase) expression, and IC50 was determined. The cytotoxicity of RDS was also determined.