2.10. Detection of SARS‐CoV‐2 spike pseudotyped virus entry into ACE2h cells

Spike pseudotyped virus entry assay was conducted as described previously (Wang, Han, et al., 2020). ACE2^h cells at the density of 5 × 10⁴ in 50 μl medium per well were seeded into 96‐well plates and cultured in 37°C for 2 h. After adherent, 25 μl of medium per well was discarded carefully, and same volume medium containing the tested drugs was added into plate for 2 h treatment. Subsequently, 5 μl of SARS‐CoV‐2 spike pseudotyped virus was added the plate and incubated at 37°C for 4 h, then 100 μl of complemented DMEM per well was added for 2 h incubation. Two hundred microliters per well of fresh DMEM medium was added to replace the culture medium containing the virus and incubated continuously at 37°C for 48 h. Twenty microliters of cell lysate was measured by the Luciferase Assay System (Promega, E1500), chemiluminescence was detected at 560 nm with a 1 s exposure time using a microplate reader.