In fact, in vitro, sACE2-spike protein complex was able to enter cells directly through receptor-mediated endocytosis via the AT1 surface receptor, or indirectly through the interaction with vasopressin and the formation of an sACE2- sACE2-spike protein-vasopressin complex, which can bind to vasopressin receptor AVPR1B allowing cell infection [138]; of note ACE2 is one of the key regulators controlling the release of vasopressin into the plasma [139]. This evidence concerns the gene ACE2 and infection.