Table 1.
Comparison of SARS‐CoV‐2, SARS‐CoV and MERS‐CoV receptors on ocular surface and lung
| Coronaviruses | Receptor | Role in human CoV disease | Ocular surface (cell types) | Lung |
|---|---|---|---|---|
|
SARS‐CoV SARS‐CoV‐2 |
ACE2 | Host cell receptor and essential for infection | + (conjunctival epithelium and fibroblasts; corneal epithelium) 31 | + (airway epithelia)32, 33 |
| TMPRSS2 | Primes spike protein for binding to ACE2 | – | + (airway epithelium) 34 | |
| CD209 | Cell‐to‐cell viral transfer | + (corneal dendritic cells) 35 | + (alveola macrophages) 36 | |
| MERS‐CoV | CD26 | Host cell receptor and essential for infection | +/− (conjunctival vascular endothelium) 37 | + (lung epithelia and endothelia) 38 |
| CD66e | Co‐receptor | +/− (palpebral conjunctiva) 39 | + (bronchial and alveolar epithelium) 32 |
+: the receptor has been found, −: there are no reports of the receptor on the ocular surface, +/−: found in tissue but only on non‐virally‐mediated inflamed tissue.