TNF and acute respiratory distress syndrome: Vascular impairment, in association with vascular endothelial growth factor, IL-6 and TNFα, is also prominent in the inflammatory phase of acute respiratory distress syndrome (ARDS) and may account for post-COVID-19 pulmonary fibrosis, which is characterized by uncontrolled fibroproliferation in the context of dysregulated release of matrix metalloproteinases, leading to injury of endothelium and epithelium [63].