TMPRSS2 and COVID-19: Several potential therapeutic targets associated with ECs for defeating COVID-19, including ACE2 [17], transmembrane protease serine 2 (TMPRSS2) [18,19], chemokine receptor 5 (CCR5) [19], IL-8 [19], CXCL-8 receptor (CXCR-2) [19], nitric oxide (NO) [20], and Neuropilin-1 [21,22].