Similar findings were noted in a non-washed in vitro infection system where 1 μM sACE2(18-611) or IFNβ-ACE2 were incubated with NL63 (MOI of 0.1) or 229E (MOI of 0.1) and then added (without virus wash) to Vero E6-TMPRSS2-T2A-ACE2 or A549 cells, respectively. Here, TMPRSS2 is linked to infection.