Effects of bone marrow-derived mesenchymal stem cells transfected with survivin on pulmonary fibrosis in mice.

The aim of the present study was to investigate the effects of bone marrow-derived mesenchymal stem cells (BMSCs) transfected with survivin on lung fibrosis in mice. Mice with bleomycin-induced pulmonary fibrosis were allocated at random to group A, B or C, and injected with 1×106 survivin gene-expressing BMSCs, 1×106 BMSCs or normal saline, respectively. A total of 6 mice were sacrificed from each group on days 7, 14 and 28 after treatment. The extent of alveolitis and pulmonary fibrosis was assessed and the apoptotic rates of the BMSCs and survivin-expressing BMSCs were detected. The content of surfactant protein A (SP-A) in the lung and hydroxyproline (Hyp) in the serum was measured. The mRNA expression levels of transforming growth factor (TGF)-β1 and matrix metalloproteinase (MMP)-9 in the lung tissue of the mice was detected. Furthermore, the protein expression levels of caspase-3 and -9 were detected. The apoptotic rates of the BMSCs (group B) and survivin-expressing BMSCs (group A) were 14.466±1.953 and 7.718±0.493%, respectively. The degree of lung fibrosis in groups A and B was reduced compared with that in group C. The hydroxyproline content in groups A and B was reduced compared with that in group C, and the SP-A content in groups A and B was increased compared with that in group C. The mRNA expression levels of TGF-β1 in group A were reduced compared with those in group B, and the levels in group B were reduced compared with those in group C. By contrast, the mRNA expression levels of MMP-9 in group A were increased compared with those in groups B and C, and the levels in group B were increased compared with those in group A. The expression levels of caspase-3 and -9 in group A were elevated compared with those in groups B and C. In conclusion, BMSCs are effective in preventing bleomycin-induced lung fibrosis, and survivin may enhance the protective effects of BMSCs.