The Effect of Different Dose of Bone Marrow-derived Mesenchymal Stem Cells on Acute Injured Lung in Rats

Objective To explore the effect and its mechanism of bone marrow mesenchymal stem cells(MSC) on rats with acute lung injury.Methods Four male Wister rats were used for collecting MSC.Female Wister rats were randomly divided into control group(C group),endotoxin lung injury group(LPS group),and MSC high-dose group(MSCH,1×106) and low-dose group(MSCL,1×105).2 mL MSC was infused intravenously and intratracheal administration of LPS one hour later.At 24 h and 72 h,samples were collected for assessment of histology,biochemical analysis and levels of TNF-α and IL-8 in bronchoalveolar lavage fluid(BALF).Results Compared with LSP group,there was a significant decrease in lung wet to dry ratio,lung injury score,WBC counts,protein levels,TNF-α and IL-8 in BALF in the MSC-treated rats at 24 h and 72 h,and the MSCH group was better than the MSCL group.Conclusion Treatment with MSC significantly reduces endotoxin-induced acute lung injury and the effect is related to its dose.