Hirai J, Kanda K, Oka T, Matsuda T
Department of Biomedical Engineering, National Cardiovascular Center Research Institute, Osaka, Japan.
ASAIO J. 1994 Jul-Sep;40(3):M383-8. doi: 10.1097/00002480-199407000-00027.
A hierarchically structured hybrid vascular tissue was prepared from vascular cells and collagen. First a hybrid medial tissue was prepared by pouring a cold mixed solution of bovine aortic smooth muscle cells (SMCs) and Type I collagen into a tubular glass mold composed of a mandrel and a sheath (inner diameter, 1.5 mm; outer diameter, 7 mm; length, 7 cm). An SMC incorporating collagenous gel was formed with incubation at 37 degrees C. After the sheath of the mold was removed, the resulting fragile tissue cultured in the medium shrank in a time dependent manner to form an opaque, dense tissue. Seeding at a higher cell density and a lower concentration of collagen resulted in rapid and prominent shrinkage. Morphologic investigation showed that with time, bipolarly elongated SMCs and collagen fiber bundles became positioned around the mandrel. When the mandrel was removed, a tubular hybrid medial tissue was formed. A hybrid vascular tissue with a hierarchical structure was constructed by seeding endothelial cells onto the inner surface of the hybrid medial tissue. Prepared tissues tolerated luminal pressures as great as 100 mmHg and mechanical stress applied during the anastomotic procedure. This method allowed the authors to prepare hybrid medial tissues of predetermined size (specifically inner diameter, wall thickness, and length) and mechanical property, which all depend on the mold design, SMC seeding density, initial collagen concentration, and incubation period. Hybrid vascular tissues may provide physiologic functions such as antithrombogenicity and regulation of vasomotor tone when implanted into a venous system.
利用血管细胞和胶原蛋白制备了一种具有分层结构的混合血管组织。首先，将牛主动脉平滑肌细胞（SMC）和I型胶原蛋白的冷混合溶液倒入由心轴和鞘管组成的管状玻璃模具（内径1.5毫米；外径7毫米；长度7厘米）中，制备混合中层组织。在37℃孵育形成含有SMC的胶原凝胶。去除模具的鞘管后，在培养基中培养的脆弱组织随时间收缩，形成不透明的致密组织。以较高的细胞密度和较低的胶原蛋白浓度接种会导致快速且明显的收缩。形态学研究表明，随着时间推移，双极伸长的SMC和胶原纤维束围绕心轴定位。去除心轴后，形成管状混合中层组织。通过将内皮细胞接种到混合中层组织的内表面构建具有分层结构的混合血管组织。制备的组织能够耐受高达100 mmHg的腔内压力以及吻合过程中施加的机械应力。该方法使作者能够制备具有预定尺寸（特别是内径、壁厚和长度）和机械性能的混合中层组织，这些均取决于模具设计、SMC接种密度、初始胶原蛋白浓度和孵育时间。将混合血管组织植入静脉系统时，可能会提供诸如抗血栓形成和血管舒缩张力调节等生理功能。
