Conclusion
Intravenous injection of hPMSCs can effectively reduce the increased pulmonary vascular endothelial permeability mediated by LPS, relieve the degree of lung tissue damage, and play a therapeutic role in ALI mice. 目的: 探讨人胎盘 MSCs（human placental MSCs，hPMSCs）移植对脂多糖诱导的急性肺损伤（acute lung injury，ALI）小鼠肺血管内皮通透性及肺组织损伤修复的影响。. 方法: 取人胎盘组织采用酶消化法分离培养 hPMSCs 并传至第 3 代，流式细胞仪检测细胞表型。将 24 只 6 周龄雄性 C57BL/6 小鼠随机分成 3 组（ n=8）。其中，ALI 模型组及 hPMSCs 治疗组采用气道滴注脂多糖方法制备 ALI 模型，对照组滴注生理盐水；滴注脂多糖 12 h 后 hPMSCs 治疗组尾静脉注射第 3 代 hPMSCs，ALI 模型组与对照组注射生理盐水。注射 24 h 后取各组小鼠肺组织，HE 染色观察肺组织病理改变，测量肺组织湿/干质量比（wet/dry mass ratio，W/D），伊文思蓝渗漏实验检测小鼠肺血管内皮通透性，Western blot 检测肺组织通透性相关蛋白血管内皮钙黏蛋白（VE-cadherin）的表达。. 结果: 流式细胞仪检测显示，分离培养的细胞具有典型 MSCs 表型特征。各组小鼠均存活。ALI 模型组肺泡结构明显塌陷、大量炎性细胞浸润、局部肺泡出血；hPMSCs 治疗组肺泡塌陷明显改善，炎性细胞浸润明显减少，肺间质有少许红细胞。ALI 模型组肺组织 W/D、伊文思蓝染液含量明显高于对照组及 hPMSCs 治疗组，hPMSCs 治疗组高于对照组，差异均有统计学意义（ P<0.05）。ALI 模型组 VE-cadherin 蛋白相对表达量明显低于对照组及 hPMSCs 治疗组，hPMSCs 治疗组低于对照组，差异均有统计学意义（ P<0.05）。. 结论: 静脉注射 hPMSCs 可有效降低脂多糖介导的肺血管内皮通透性增加，减轻肺组织损伤程度，对小鼠 ALI 具有治疗作用。.
Methods
The hPMSCs were isolated from the human placental tissue by enzyme digestion and passaged. The cell phenotype of the 3rd generation hPMSCs was detected by flow cytometry. Twenty-four 6-week-old healthy male C57BL/6 mice were randomly divided into 3 groups ( n=8). The mice were instilled with LPS in the airway to prepare an ALI model in the ALI model group and the hPMSCs treatment group, and with saline in the control group. At 12 hours after LPS infusion, the mice were injected with 3rd generation hPMSCs via the tail vein in hPMSCs treatment group and with saline in the ALI model group and the control group. At 24 hours after injection, the lung tissues of all mice were taken. The pathological changes were observed by HE staining. The wet/dry mass ratio (W/D) of lung tissue was measured. The Evans blue leak test was used to detect the pulmonary vascular endothelial permea bility in mice. The expression of lung tissue permeability-related protein (VE-cadherin) was detected by Western blot.
Objective
To investigate the effects of human placental mesenchymal stem cells (hPMSCs) transplantation on pulmonary vascular endothelial permeability and lung injury repair in mice with lipopolysaccharide (LPS)-induced acute lung injury (ALI).
Results
Flow cytometry examination showed that the isolated cells had typical MSCs phenotypic characteristics. Mice in each group survived. The alveolar structure of the ALI model group significantly collapsed, a large number of inflammatory cells infiltrated, and local alveolar hemorrhage occurred; while the alveolar structure collapse of the hPMSCs treatment group significantly improved, inflammatory cells infiltration significantly reduced, and a few red blood cells were in the interstitial lung. W/D and exudation volume of Evans blue stain were significantly higher in the ALI model group than in the control group and the hPMSCs treatment group ( P<0.05), in the hPMSCs treatment group than in the control group ( P<0.05). The relative protein expression of VE-cadherin was significantly lower in the ALI model group than in the control group and the hPMSCs treatment group ( P<0.05), and in the hPMSCs treatment group than in the control group ( P<0.05).