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]. The gene discussed is CD4; the disease is acute respiratory distress syndrome.