Jeong Sung In, Kim So Yeon, Cho Seong Kwan, Chong Moo Sang, Kim Kyung Soo, Kim Hyuck, Lee Sang Bong, Lee Young Moo
School of Chemical Engineering, College of Engineering, Hanyang University, Seoul 133-791, Republic of Korea.
Biomaterials. 2007 Feb;28(6):1115-22. doi: 10.1016/j.biomaterials.2006.10.025. Epub 2006 Nov 16.
Novel tubular scaffolds of marine source collagen and PLGA fibers were fabricated by freeze drying and electrospinning processes for vascular grafts. The hybrid scaffolds, composed of a porous collagen matrix and a fibrous PLGA layer, had an average pore size of 150+/-50 microm. The electrospun fibrous PLGA layer on the surface of a porous tubular collagen scaffold improved the mechanical strength of the collagen scaffolds in both the dry and wet states. Smooth muscle cells (SMCs)- and endothelial cells (ECs)-cultured collagen/PLGA scaffolds exhibited mechanical properties similar to collagen/PLGA scaffolds unseeded with cells, even after culturing for 23 days. The effect of a mechanical stimulation on the proliferation and phenotype of SMCs and ECs, cultured on collagen/PLGA scaffolds, was evaluated. The pulsatile perfusion system enhanced the SMCs and ECs proliferation. In addition, a significant cell alignment in a direction radial to the distending direction was observed in tissues exposed to radial distention, which is similar to the phenomenon of native vessel tissues in vivo. On the other hand, cells in tissues engineered in the static condition were randomly aligned. Immunochemical analyses showed that the expressions of SM alpha-actin, SM myosin heavy chain, EC von Willebrand factor, and EC nitric oxide were upregulated in tissues engineered under a mechano-active condition, compared to vessel tissues engineered in the static condition. These results indicated that the co-culturing of SMCs and ECs, using collagen/PLGA hybrid scaffolds under a pulsatile perfusion system, leads to the enhancement of vascular EC development, as well as the retention of the differentiated cell phenotype.
通过冷冻干燥和静电纺丝工艺制备了新型的海洋源胶原蛋白和聚乳酸-羟基乙酸共聚物（PLGA）纤维管状支架用于血管移植。这种混合支架由多孔胶原基质和纤维状PLGA层组成，平均孔径为150±50微米。多孔管状胶原支架表面的静电纺丝纤维状PLGA层在干态和湿态下均提高了胶原支架的机械强度。即使培养23天后，培养了平滑肌细胞（SMCs）和内皮细胞（ECs）的胶原/PLGA支架的力学性能与未接种细胞的胶原/PLGA支架相似。评估了机械刺激对培养在胶原/PLGA支架上的SMCs和ECs增殖及表型的影响。脉动灌注系统促进了SMCs和ECs的增殖。此外，在受到径向扩张的组织中观察到细胞沿与扩张方向径向的方向显著排列，这与体内天然血管组织的现象相似。另一方面，在静态条件下构建的组织中的细胞随机排列。免疫化学分析表明，与在静态条件下构建的血管组织相比，在机械活性条件下构建的组织中平滑肌α-肌动蛋白、平滑肌肌球蛋白重链、内皮细胞血管性血友病因子和内皮细胞一氧化氮的表达上调。这些结果表明，在脉动灌注系统下使用胶原/PLGA混合支架共培养SMCs和ECs，可促进血管内皮细胞的发育，并保留分化细胞的表型。
