ACTA1 and pulmonary fibrosis: The proliferated MFs can be further activated by NETs to over‐express α‐smooth muscle actin (α‐SMA) and extracellular matrix (ECM) proteins, causing pulmonary fibrosis.[6] Meanwhile, the DNAs of NETs may activate Toll‐like receptor 9 (TLR9) of immune cells as damage‐associated molecular patterns (DAMPs).