A recent study demonstrated that intrapulmonary delivery of human UC-MSCs attenuates acute lung injury by expanding CD4 + CD25+ Forkhead Boxp3(FOXP3) + regulatory T Cells, despite different cytokines detected, they also confirmed the balance effect of UC-MSCs on pro- and anti- inflammatory cytokines in ALI[44]. Here, FOXP3 is linked to acute respiratory distress syndrome.