At a multiplicity of infection (MOI) of 0.1, the cell line minimally affected binding, with isolates 4 and 5 having significantly lower binding in the TMPRSS2 cell line (P = 0.013, P = 0.0045, respectively), suggesting that all isolates were binding efficiently to the endogenously expressed primate ACE2 on the VeroE6-TMPRSS2 cells. The gene discussed is ACE2; the disease is infection.