中文摘要：

背景：理想的组织工程尿道替代物应具有良好的力学特性，足以承受长时间的尿液排泄冲击，而静态培养的尿路肌性管腔强度不佳。已有研究表明，力学刺激能够促进细胞生长和细胞外基质的分泌。 目的：探讨生物反应器内构建组织工程化尿路肌性管腔的可行性。 方法：酶消化法获取脂肪干细胞，经体外培养和扩增后，流式细胞技术检测细胞表面抗原，将脂肪干细胞接种于聚羟基乙酸上，形成细胞-材料复合物，体外培养1周后，将其置于生物反应器内培养，实验组予以动态力学刺激培养；对照组为静态培养，先采用基础培养基培养3周，而后用成肌诱导培养液诱导4周，行大体观察及组织学检测。 结果与结论：流式细胞仪检测细胞表面CD90，CD44，CD105表达率分别为99.42%，98.12%，93.27%；CD34，CD45表达率分别为4.92%和0.38%，实验组培养的肌性管腔色泽明亮，管腔圆润，免疫组化染色显示，细胞材料复合物在诱导4周后，细胞表达结蛋白和α-平滑肌肌动蛋白阳性，细胞材料复合物胶原成分多。对照组构建的肌性管腔色泽暗淡，管腔轻度塌陷，细胞材料复合物胶原成分较少。提示脂肪干细胞复合聚羟基乙酸材料在生物反应器内动态培养可构建具有良好结构的尿路肌性管腔。

英文摘要：

BACKGROUND： Ideal tissue-engineered urinary tract should have good mechanical properties to bear long-term attack of urine and excretion. Muscular conduit of urinary tract in static culture exerts poor strength. It is reported that mechanical stimuli promote cellular growth and secretion of extracellular matrix. OBJECTIVE： To investigate the feasibility of constructing tissue-engineered muscular conduit of urinary tract in bioreactor. METHODS： Adipose-derived stem cells were harvested by collagen enzyme method. After series culture and expansion in vitro, flow cytometric analysis was carried out to detect the immunophenotypes of adipose-derived stem cells. Then the cell-polyglycolic acid complex was constructed by seeding adipose-derived stem cells on polyglycolic acid fibers. After 1 week of in vitro culture, cell-polyglycolic acid complex was cultured in a bioreactor. The experimental group was subjected to pulsatile stimuli, while the control group was cultured in static state. After 3 weeks of in vitro culture in basic medium, the cell-polyglycolic acid complex was induced in the induced culture medium for 4 weeks, and then engineered tissue was examined both grossly and histologically. RESULTS AND CONCLUSION： Flow cytometry demonstrated that the adipose-derived stem cells expressed CD90 （99.42%）, CD44 （98.12%） and CD105 （93.27%）, but not CD34 （4.92%） or CD45 （0.38%）. In the experimental group, tissue-engineered muscular conduit of urinary tract appeared bright color with a round lumen. Immunohistochemical staining showed that after cell-polyglycolic acid complex was induced for 4 weeks, the cells expressed desmin and α-smooth muscle actin. More collagen was found in the complex. In contrast, the control group appeared pale surface and its lumen collapsed slightly. Less collagen was in the complex. Tissue-engineered muscular conduit of urinary tract with good structure can be constructed in a bioreactor.