Fig. 2.

Healthy alveoli versus damaged alveoli in SARS-CoV-2 infection. Depicted the normal alveoli with coordinated functions (left), and damaged alveoli in SARS-CoV-2 infection (right). The wide cytokines production following immune activation through PAMPs or DAMPs, which recruited more immune cells to the infection site, such as neutrophils and lymphocytes, triggers an inflammatory cascade leading to asynchronized immune responses and ultimately to the pyroptosis of the pneumocytes