IL4 and acute respiratory distress syndrome: The prevalence of Th2 (CD4+ IL-4+/CD4+ T cells) in peripheral blood was significantly higher in ALI 24 h group than that in normal control group (Con group: 6.8 ± 1.3%, ALI 24 h group: 12 ± 0.68%, P = 0.0037, Supplementary Fig. S2).