肺祖细胞抑制博来霉素诱导的小鼠肺纤维化OA

Objective To investigate the colonization of lung progenitor cells in the lungs of mice and their effects on mice pulmonary fibrosis.Methods Human embryonic stem cells were differentiated into lung progenitor cells in vitro,identified by immunofluorescence and cell flow cytometry,and transplanted into the lungs of normal immunodeficient mice.The time of colonization and the ability to differentiate into mature lung epithelial cells in vivo were observed.Immunodeficient mice were perfused with bleomycin(2 μg/10 g)through the air duct to establish a pulmonary fibrosis model,and lung progenitor cells were transplanted into the lungs of the mice with fibrosis.After treatment,lung tissue was sliced for hematoxylin-eosin staining and Masson staining,and changes of low α-smooth muscle actin(α-SMA),extracellular matrix protein 1(ECM-1),and hydroxyproline expressions in lung and apoptosis were also tested.Results Immunofluorescence and cell flow cytometry showed that the expression rate of the definitive endoderm cell stage markers,forkhead box protein A2 and chemokine receptor 4,could reach over 90%.The lung progenitor cell marker NKX2.1 showed a differentiation efficiency of 70%for lung progenitor cells.At 4 weeks after transplantation,lung progenitor cells that were colonized in the lungs of immunodeficient mice were found,but no expression of surfactant protein C was found in lung progenitor cells.After perfusion of lung progenitor cells,there were statistical differences in the Ashcroft score,α-SMA and ECM-1 that reflect the degree of pulmonary fibrosis between the groups(P<0.01).There was a difference in the fluorescence area of surfactant protein C that reflected the function of pulmonary epithelium between the groups(P<0.01).There was a difference in the concentration of hydroxyproline that reflected the level of collagen between the groups(P<0.01).There was a difference in the fluorescence areas between the groups in the in situ terminal deoxynucleotidyl transferase labeling technique staining experiment(P<0.01).Conclusion Lung progenitor cells can be colonized in the lungs of immunodeficient mice and cannot differentiate into mature lung epithelial cells,but can inhibit the progression of pulmonary fibrosis.