CXCL8 and acute respiratory distress syndrome: Moreover, recent studies showed that ALI/ARDS increased the release of proinflammatory cytokines, such as tumor necrosis factor (TNF-α), interleukin (IL)-1β, IL-6, and IL-8 from immune cells [15,16], and increased the permeability of the alveolar–capillary barrier [8,17].