Fig. 3.

Gene expression levels of host factors involved in SARS-CoV-2 entry

(A-D) Relative expression levels of ACE2 (A), NRP1 (B), cathepsin L (C) and TMPRSS2 (D) in A549 cells during the adaptation to ALI culture were measured by qRT-PCR. β-actin mRNA levels were used as the reference control. (E) ALI-cultured A549 cells were infected with SARS-CoV-2 in the presence of 50 μM camostat. Viral RNA levels at 6 hpi were measured by qRT-PCR and normalized to the expression levels of β-actin. The values in the graphs are expressed as the mean ± SD of triplicate samples. ∗∗p < 0.01, two-tailed Student's t-test.