低分子凝胶M2和交联透明质酸作为可注射性软骨再生支架的可行性研究

目的 探讨以低分子量凝胶M2和交联透明质酸（Hyaluronic acid,HA）作为可注射性支架材料,在裸鼠体内构建组织工程软骨的可行性。方法 常规分离、体外单层培养新生猪耳软骨细胞,将获得的软骨细胞以50×10^6 cells/m L和100×10^6cells/m L的浓度分别与M2凝胶混合,以100×10^6 cells/m L的浓度与交联HA混合,分别注射于裸鼠皮下,并于8周后取材。以单纯M2凝胶及单纯HA作为对照组。通过大体观察、组织化学检查、湿重测定、力学检测、蛋白聚糖（Glycosaminoglycan,GAG）含量测定,判断低分子量凝胶M2及交联透明质酸在体内形成软骨的能力。结果实验组3组均可形成软骨样组织块。其中,M2＋高浓度细胞组体积最大、质地较硬、表面光滑,软骨细胞位于成熟的陷窝中;M2＋低浓度细胞组形成与高浓度细胞组质地相似的组织块,但体积相对较小;HA组形成不成熟的组织块,硬度差,含有的细胞数和分泌的基质最少。同时,实验组3组的力学和GAG含量结果也证实M2＋高浓度细胞形成的软骨更加成熟。各组间具有显著性差异。2个对照组未有类软骨组织形成。结论 低分子凝胶M2与软骨细胞的生物相容性优于交联HA,更适合作为可注射性支架材料用于组织工程化软骨的构建。

Low-Molecule-Weight Hydrogel M2 and Cross-Lincked Hyaluronic Acid as Injectable Cartilage Regeneration Scaffolds

Objective To explore the feasibility of low-molecule-weight hydrogel M2 and cross-lincked hyaluronic acid （HA） as injectable materials for cartilage tissue engineering in nude mice. Methods The auricular chondrocytes of newborn pig were isolated and expanded. The cells were mixed with M2 hydrogel in 50×10^6 cells/mL and 100×10^6 cells/mL, and were mixed with HA in 100 ×10^6 cells/mL, followed by subcutaneous injection into nude mice. M2 hydrogel and HA were also injected as control groups. After 8 weeks, the samples were harvested and evaluated for cartilage formation by gross view, histochemical examination, wet weight test, mechanical analysis and glycosaminoglycan （GAG） quantification. Results All three groups formed cartilage-like tissues. Samples in M2 group with high cell density （100×10^6 cells/mL） were the largest in size with stiffest texture, smoothest surface, and most abundant lacuna structures. Samples in M2 group with low cell density （50 ×10^6 cells/mL） also formed cartilage-like tissue with stiff texture, but their size shrank obviously; HA group, however, formed immature cartilaginous tissue with poor rigidity, cellularization and cartilage specific matrix expression. The corresponding quantitative data further demonstrated that samples in M2 group with high cell density had the highest GAG content and strongest mechanical property. Statistically significant differences were observed among 3 groups. No cartilage-like tissue were formed in the 2 control groups. Conclusion Low-molecule-weight hydrogel M2 has better biocompatibility than hyaluronic acid, and M2 can be more suitable for TE cartilage construction.