The clathrin‐mediated pathway involves the binding of CoV S protein to the host receptor followed by the internalization of vesicles that maturate to late endosomes. Acidification of the endosome promotes the H+‐dependent activation of cellular cathepsin L proteinase in late endosomes and lysosomes, which cleaves and activates the S protein, thus initiating viral fusion. Recent research shows that in addition to ACE2 SARS‐CoV‐2 can also use the host cell receptor CD147 to gain access into host cells. 100