TMPRSS2 and infection: The goals of our study were 2-fold: (1) identify host miRNAs that may directly bind to SARS-CoV-2 genomic RNA and thus affect viral infectivity; and (2) identify host miRNAs that may regulate ACE2 and TMPRSS2 expression, or their upstream interferon (IFN) regulators, and thus control the susceptibility of cells to infection by SARS-CoV-2.