Yet, this earlier evidence supporting downregulation of ACE2 during COVID-19 is challenged by recent findings that upregulated activity of ADAM17, a membrane-bound metalloproteinase, can cleave membrane ACE2, thus leading to upregulated systemic levels and activity of soluble ACE2 during SARS-CoV-2 infection [30,31]. This evidence concerns the gene ADAM17 and COVID-19.