Using this lung chip, more detailed information and new phenomena during influenza virus and SARS-CoV-2 infection can be achieved, and cytokine M-CSF may be identified as a candidate marker indicating chronic obstructive pulmonary disease (COPD) caused by respiratory viruses (Benam et al., 2016; Si et al., 2019). Here, CSF1 is linked to chronic obstructive pulmonary disease.