Fig. 2From: Sex differences in severity and mortality from COVID-19: are males more vulnerable?Coronavirus entry into cell. Coronavirus spike protein binds to ACE2 on the human cell surface. TMPRSS2 cleaves spike protein to help virus fusion and entry inside the target cell. ADAM17 can cleave ACE2 and release the ectodomain as a soluble form. The soluble form can bind to virus and can help to prevent infectionBack to article page