These cell lines included Raji cells that were confirmed to exhibit FcγR2B expression, which contributes to the enhancement of SARS-CoV-2 infection (37, 46), and THP-1 cells were confirmed to exhibit FcγR2A expression, which contributes to enhancement of MERS-CoV (47) and SARS-CoV-1 (5, 48) infection. This evidence concerns the gene FCGR2A and infection.