HMGB1 and acute respiratory distress syndrome: In this article, we summarize the role of p38MAPK in the development and occurrence of ARDS, including its regulation of the expression and activity of the inflammatory mediators ICAM-1, HMGB1, and ET-1; neutrophil chemotaxis and apoptosis; the balance of Treg/Th17 cells; and the PMVECs apoptosis.