Thus, our hypothesis is that not only KRT5+TP63+ basal cells, but also AQP3+ basal-like cells, proliferated abnormally to fill the alveolar space and stroma tissue that was collapsed upon SARA-CoV-2 infection, and suppression of the increase in KRT5+TP63+ basal cells and/or AQP3+ basal-like cells might retain a normal inflammatory defending response and facilitate the regeneration of airway alveolar epithelial cells. Here, KRT5 is linked to COVID-19.