中文摘要：

目的研究骨髓间充质干细胞（BMSCs）移植对染矽尘小鼠肺部早期炎症的影响。方法取5只无特定病原体级健康雄性C57BL/6小鼠,采用全骨髓贴壁法分离培养BMSCs。取30只同类小鼠随机分为对照组、二氧化硅组和BMSCs移植组3组,以气管暴露法建立动物模型,对照组小鼠予气管内一次性注射0.90%氯化钠溶液20.0μL;二氧化硅组和BMSCs移植组小鼠先予气管内一次性注射20.0μL质量浓度为250 g/L的二氧化硅混悬液,6 h后再分别经尾静脉输注500.0μL的0.90%氯化钠溶液或细胞密度为1×10^9/L的BMSCs悬液。造模后第7天处死小鼠,观察肺组织病理学改变情况,采用酶联免疫吸附实验检测小鼠血清中白细胞介素（IL）-1β、IL-6和IL-10水平,采用实时定量聚合酶链反应仪检测小鼠肺组织中上述细胞因子mRNA的表达情况。结果 BMSCs表面分子分化抗原（CD）29、CD34、CD90、CD105、CD106的阳性率分别为67.70%、0.12%、39.00%、37.10%和20.10%。肺组织病理学观察显示,二氧化硅组小鼠肺泡壁增厚,肺泡间隔增宽,肺泡结构破坏;BMSCs移植组肺组织结构无明显破坏,肺泡腔大小均匀,肺泡结构完整。二氧化硅组小鼠血清中IL-1β、IL-6水平以及肺组织中IL-1β、IL-6 mRNA相对表达水平分别高于对照组和BMSCs移植组（P〈0.05）,BMSCs移植组小鼠血清中IL-1β水平和肺组织中IL-1βmRNA相对表达水平均高于对照组（P〈0.05）。各组小鼠血清中IL-10水平和肺组织中IL-10 mRNA相对表达水平分别比较,差异均无统计学意义（P〉0.05）。结论 BMSCs可通过下调促炎因子IL-1β和IL-6的表达减轻染矽尘小鼠肺部早期炎性损伤。

英文摘要：

Objective To study the effects of bone marrow mesenchymal stem cell（ BMSC） transplantation on early stage of inflammation in mice exposed to silica dust. Methods Specific pathogen free healthy male C57 BL /6 mice were used.Five mice were used to isolate BMSCs using bone marrow adherent method. Thirty mice were randomly divided into 3groups： control group,silica group and BMSCs transplantation group. The mice of the control group were given 20. 0 μL of0. 90% sodium chloride solution by one time intratracheal injection. The mice of silica group and the BMSCs transplantation group first received 20. 0 μL（ 250 g / L mass concentration） of silicosis dust suspension by one time intratracheal injection; followed by 500. 0 μL of 0. 90% sodium chloride solution in the silica group,and 500. 0 μL of BMSCs suspension（ cell density 1 ×10^9/ L） by tail vein infusion in the BMSCs transplantation group 6 hours later. Mice were euthanized on the 7th day of the experiments. The histopathology changes in lung tissues were examined. The serum levels of interleukin（ IL）-1β, IL-6 and IL-10 were detected by enzyme linked immunosorbent assay. Real-time quantitative polymerase chain reaction was used to detect the mRNA relative expression levels of above cytokines in the lung tissues. Results The positive rates of BMSCs surface molecules cluster differentiation（ CD） 29,CD34,CD90,CD105 and CD106 were 67. 70%,0. 12%,39. 00%,37. 10% and 20. 10%,respectively. Histopathology examination showed the thickened alveolar walls,broadening alveolar septum and the damaged alveolar structure in silica group. In the BMSCs transplantation group,there was no obvious damage found in the lung tissue. There was no change in the alveolar cavity and alveolar structure was complete. The IL-1β and IL-6 levels in serum and mRNA relative expression of IL-1β and IL-6in lung tissue in the silica group were higher than those of the control group and BMSCs transplantation group（ P〈0. 05）.The IL-1β level in serum and mRNA relative