TNF and acute respiratory distress syndrome: In addition, increased apoptosis of AECs and alveolar macrophages can be observed, which results in the release of tumor necrosis factor-α (TNF-α) and transforming growth factor-β1, resulting in inflammation and progression from ARDS to fibrosis (Chapman 1999; Yang et al. 2018; Cui et al. 2020; Zhou et al. 2020a).