Background: The cartilage tissue lacks blood vessels, which is composed of chondrocytes and ECM. Due to this vessel-less structure, it is difficult to repair cartilage tissue damages. One of the new methods to repair cartilage damage is to use tissue engineering. In the present study, it was attempted to simulate a three-dimensional environment similar to the natural ECM of cartilage tissue by using hydrogels made of natural materials, including Chitosan and different ratios of Alginate.Material and methods: Chitosan, alginate and Chitosan/Alginate hydrogels were fabricated. Fourier Transform Infrared, XRD, swelling ratio, porosity measurement and degradation tests were applied to scaffolds characterization. After that, human adipose derived-mesenchymal stem cells (hADMSCs) were cultured on the hydrogels and then their viability and chondrogenic differentiation capacity were studied. Safranin O and Alcian blue staining, immunofluorescence staining and real time RT-PCR were used as analytical methods for chondrogenic differentiation potential evaluation of hADMSCs when cultured on the hydrogels.Results: The highest degradation rate was detected in Chitosan/Alginate (1:0.5) group The scaffold biocompatibility results revealed that the viability of the cells cultured on the hydrogels groups was not significantly different with the cells cultured in the control group. Safranin O staining, Alcian blue staining, immunofluorescence staining and real time PCR results revealed that the chondrogenic differentiation potential of the hADMSCs when grown on the Chitosan/Alginate hydrogel (1:0.5) was significantly higher than those cell grown on the other groups.Conclusion: Taken together, these results suggest that Chitosan/Alginate hydrogel (1:0.5) could be a promising candidate for cartilage tissue engineering applications.

中文翻译：

---

天然水凝胶促进人间充质干细胞的软骨分化

背景：软骨组织缺乏血管，由软骨细胞和ECM组成。由于这种无血管结构，软骨组织损伤很难修复。修复软骨损伤的新方法之一是使用组织工程。本研究尝试利用天然材料（包括壳聚糖和不同比例的海藻酸盐）制成的水凝胶来模拟类似于软骨组织天然ECM的三维环境。材料和方法：壳聚糖、海藻酸盐和壳聚糖/海藻酸盐制备了水凝胶。傅立叶变换红外、X射线衍射、溶胀比、孔隙率测量和降解测试应用于支架表征。之后，在水凝胶上培养人脂肪源间充质干细胞（hADMSC），然后研究其活力和软骨分化能力。采用番红O和阿尔新蓝染色、免疫荧光染色和实时RT-PCR作为分析方法，评价hADMSCs在水凝胶上培养时的成软骨分化潜力。结果：在壳聚糖/海藻酸盐（1:0.5）中检测到最高的降解率支架生物相容性结果显示，水凝胶组培养的细胞活力与对照组培养的细胞没有显着差异。番红O染色、阿尔新蓝染色、免疫荧光染色和实时PCR结果显示，在壳聚糖/海藻酸盐水凝胶（1:0.5）上生长的hADMSCs的成软骨分化潜力显着高于在其他组上生长的细胞。 结论：总而言之，这些结果表明壳聚糖/海藻酸盐水凝胶 (1:0.5) 可能是软骨组织工程应用的有希望的候选者。