ACE2 and severe acute respiratory syndrome: Single‐cell RNA‐seq data analysis of angiotensin‐converting enzyme II (ACE2) expression and serological investigation of patient samples have indicated that ACE2 may be the cell receptor of SARS‐CoV‐2,11, 12 thus suggesting that ACE2‐expressing cells are likely to be the major target cell type which are vulnerable to SARS‐CoV‐2 infection.