Wang Chen-Chie, Yang Kai-Chiang, Lin Keng-Hui, Wu Chang-Chin, Liu Yen-Liang, Lin Feng-Huei, Chen Ing-Ho
Department of Orthopedic Surgery, Taipei Tzu Chi Hospital, The Buddhist Tzu Chi Medical Foundation, New Taipei City, Taiwan; Department of Orthopedics, School of Medicine, Tzu Chi University, Hualien, 97004, Taiwan.
Biotechnol Bioeng. 2014 Nov;111(11):2338-48. doi: 10.1002/bit.25295. Epub 2014 Sep 10.
A tissue engineering chondrocytes/scaffold construct provides a promise to cartilage regeneration. The architecture of a scaffold such as interconnections, porosities, and pore sizes influences the fates of seeding cells including gene expression, survival, migration, proliferation, and differentiation thus may determine the success of this approach. Scaffolds of highly ordered and uniform structures are desirable to control cellular behaviors. In this study, a newly designed microfluidic device based on flow-focusing geometry was developed to fabricate gelatin scaffolds of ordered pores. In comparison with random foam scaffolds made by the conventional freeze-dried method, honeycomb-like scaffolds exhibit higher swelling ratio, porosity, and comparable compressive strength. In addition, chondrocytes grown in the honeycomb-like scaffolds had good cell viability, survival rate, glycosaminoglycans production, and a better proliferation than ones in freeze-dried scaffolds. Real-time PCR analysis showed that the mRNA expressions of aggrecan and collagen type II were up-regulated when chondrocytes cultured in honeycomb-like scaffolds rather than cells cultured as monolayer fashion. Oppositely, chondrocytes expressed collagen type II as monolayer culture when seeded in freeze-dried scaffolds. Histologic examinations revealed that cells produced proteoglycan and distributed uniformly in honeycomb-like scaffolds. Immunostaining showed protein expression of S-100 and collagen type II but negative for collagen type I and X, which represents the chondrocytes maintained normal phenotype. In conclusion, a highly ordered and honeycomb-like scaffold shows superior performance in cartilage tissue engineering. Biotechnol. Bioeng. 2014;111: 2338-2348. © 2014 Wiley Periodicals, Inc.
一种组织工程软骨细胞/支架构建体为软骨再生带来了希望。支架的结构，如互连性、孔隙率和孔径，会影响接种细胞的命运，包括基因表达、存活、迁移、增殖和分化，因此可能决定这种方法的成败。具有高度有序和均匀结构的支架对于控制细胞行为是理想的。在本研究中，开发了一种基于流动聚焦几何结构新设计的微流控装置，以制造具有有序孔隙的明胶支架。与通过传统冷冻干燥方法制备的随机泡沫支架相比，蜂窝状支架表现出更高的溶胀率、孔隙率和相当的抗压强度。此外，在蜂窝状支架中生长的软骨细胞具有良好的细胞活力、存活率、糖胺聚糖产量，并且比冷冻干燥支架中的软骨细胞具有更好的增殖能力。实时PCR分析表明，当软骨细胞在蜂窝状支架中培养时，聚集蛋白聚糖和II型胶原蛋白的mRNA表达上调，而不是以单层方式培养的细胞。相反，当接种在冷冻干燥支架中时，软骨细胞以单层培养方式表达II型胶原蛋白。组织学检查显示，细胞产生蛋白聚糖并均匀分布在蜂窝状支架中。免疫染色显示S-100和II型胶原蛋白的蛋白表达，但I型和X型胶原蛋白为阴性，这表明软骨细胞维持正常表型。总之，高度有序的蜂窝状支架在软骨组织工程中表现出卓越的性能。《生物技术与生物工程》2014年；111: 2338 - 2348。© 2014威利期刊公司
