Fig. 3.

The SARS-CoV-2 spike protein S1 does not promote the phosphorylation of MEK in the presence of the neutralizing antibody against ACE2. Human pulmonary artery smooth muscle cells were pre-treated with the ACE2 antibody for 1 h and then treated with recombinant full length S1 subunit of the SARSCoV-2 spike protein (Val16 – Gln690) for 10 min. Cell lysates were prepared and subjected to Western blotting using antibodies against phosphorylated MEK (p-MEK) and MEK protein. The bar graph represents means ± SEM (N = 4).*Significantly different from untreated control at p < 0.05. NS denotes that the two values are not significantly different from each other at p < 0.05.