SARS-CoV-2 Spike Protein Fusion Assay

Fusion assay was performed according to a previously published report^{8 (link)}. Briefly, A549 cells transduced with eGFP-luciferase-SARS-CoV-2 spike S1 lentivirus vector (GenScript, Piscataway, NJ) were detached with 1 mM EDTA, treated with selected FAs at 20–160 µg/ml (linolenic acid: 71.8–574.7 mM, EPA: 66.1–529.1 mM) concentrations for 1 h at 37 °C and overlaid on 95% confluent human A567 lung epithelial cells overexpressing hACE2. After 4 h’ incubation at 37 °C, images of syncytia were captured with a Zeiss Axio Observer A1 fluorescence microscope (Carl Zeiss Meditec, Inc, Dublin, CA). All experiments were done in triplicate and repeated three times. The positive control was 20 μg/ml anti-ACE2 antibody. Results are expressed as a percentage of experimental lipid-free control (mean + /− SD, n = 3).