ACE2 and infection: African green monkey kidney epithelial VeroE6, human lung epithelial A549-ACE2, human lung fibroblast MRC5-ACE2, human kidney HEK293T-ACE2, and human bronchial epithelial 16HBE cells were infected with SARS-CoV-2 HK at a multiplicity of infection (MOI) of 1 in a synchronized manner by keeping infections for 1 h at 4°C.