Abstract：
The objectives of this study were to compare the chondrogenic potential of cells derived from different layers of Mandibular condyle cartilage and to gain further understanding of the impact of chondrogenic cues when embedded into a novel hydrogel scaffold (PGH, a polymer blend of poly (ethylene glycol), gelatin, and heparin) compared to a gelatin hydrogel scaffold (GEL). Cartilage layer cells (CLCs) and fibroblastic superficial layer cells (SLCs) were harvested from the mandibular condyle of boer goats obtained from a local abattoir. After expansion, cells were seeded into PGH and GEL hydrogels and cultured in chondrogenic media for 3 weeks. Scaffolds were harvested at 0, 1, and 3 week(s) and processed for gross appearance, histochemical, biochemical, and mechanical assays. In terms of chondrogenesis, major differences were observed between scaffold materials, but not cell types. Glycosaminoglycan (GAG) staining showed GEL scaffolds deposited GAG during the 3 week period, which was also confirmed with the biochemical testing. Moreover, GEL scaffolds had significantly higher compressive modulus and peak stress than PGH scaffolds at all time points with the largest difference seen in week 3. It can be concluded that GEL outperformed PGH in chondrogenesis. It can also be concluded that materials play a more important role in the process of chondrogenesis than the tested cell populations. Fibroblastic SLCs were shown to have similar chondrogenic potential as CLCs cells, suggesting a rich pool of progenitor cells in the superficial fibroblastic layer capable of undergoing chondrogenesis given appropriate physical and chemical cues.
摘要：
本研究的目的是比较来自下颌髁突软骨不同层的细胞的软骨形成潜能，并进一步了解嵌入新型水凝胶支架（PGH，聚（乙二醇）的聚合物共混物，明胶,和肝素）与明胶水凝胶支架（GEL）相比。软骨层细胞（CLC）和成纤维细胞浅层细胞（SLC）是从当地屠宰场获得的波尔山羊的下颌髁中收获的。扩展后,将细胞接种到PGH和GEL水凝胶中,并在软骨形成培养基中培养3周。在第0周、第1周和第3周收获支架，并处理其外观，组织化学,生物化学，和机械化验。在软骨形成方面，观察到支架材料之间的主要差异，但不是细胞类型。糖胺聚糖（GAG）染色显示GEL支架在3周内沉积GAG，生化测试也证实了这一点。此外，在所有时间点,GEL支架具有显著高于PGH支架的压缩模量和峰值应力,在第3周观察到最大差异。可以得出结论，GEL在软骨形成中优于PGH。还可以得出结论，与测试的细胞群相比，材料在软骨形成过程中起着更重要的作用。成纤维细胞SLC与CLC细胞具有相似的软骨形成潜能，提示浅层成纤维细胞中有丰富的祖细胞库，能够在适当的物理和化学线索下进行软骨形成。
