Under appropriate culture conditions, mesenchymal stem cells (MSC), also called more properly multipotent mesenchymal stromal cells (MMSC), can be induced toward differentiation into different cell lineages. In order to guide stem cell fate within an environment resembling the stem cell niche, different biomaterials are being developed. In the present study, we used silk fibroin (SF) as a biomaterial supporting the growth of MMSC and studied its effect on chondrogenesis of canine adipose-derived MMSC (cADMMSC). Adipose tissue was collected from nine privately owned dogs. MMSC were cultured on SF films and SF scaffolds in a standard cell culture medium. Cell morphology was evaluated by scanning electron microscopy (SEM). Chondrogenic differentiation was evaluated by alcian blue staining and mRNA expression of collagen type 1, collagen type 2, Sox9, and Aggrecan genes. cADMMSC cultured on SF films and SF scaffolds stained positive using alcian blue. SEM images revealed nodule-like structures with matrix vesicles and fibers resembling chondrogenic nodules. Gene expression of chondrogenic markers Sox9 and Aggrecan were statistically significantly upregulated in cADMMSC cultured on SF films in comparison to negative control cADMMSC. This result suggests that chondrogenesis of cADMMSC could occur when cells were grown on SF films in a standard cell culture medium without specific culture conditions, which were previously considered necessary for induction of chondrogenic differentiation.

中文翻译：

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丝素蛋白诱导犬脂肪来源的多能间充质基质细胞/间充质干细胞的软骨分化。

在适当的培养条件下，可以诱导间充质干细胞（MSC），也称为更适当的多能间充质基质细胞（MMSC），以分化为不同的细胞谱系。为了在类似于干细胞利基的环境中引导干细胞的命运，正在开发不同的生物材料。在本研究中，我们使用丝素蛋白（SF）作为支持MMSC生长的生物材料，并研究了其对犬脂肪来源MMSC（cADMMSC）软骨形成的影响。从九只私人狗中收集脂肪组织。将MMSC在标准细胞培养基中的SF膜和SF支架上培养。通过扫描电子显微镜（SEM）评估细胞形态。通过阿尔辛蓝染色和1型胶原，2型胶原，Sox9，和Aggrecan基因。培养于SF膜上的cADMMSC和SF支架使用阿尔辛蓝染色呈阳性。SEM图像显示结节状结构，基质囊泡和纤维类似于软骨结节。与阴性对照cADMMSC相比，在SF膜上培养的cADMMSC中，软骨生成标记Sox9和Aggrecan的基因表达在统计学上显着上调。该结果表明，当细胞在没有特定培养条件的标准细胞培养基中的SF膜上生长时，可能会发生cADMMSC的软骨形成，以前认为这是诱导软骨分化的必要条件。与阴性对照cADMMSC相比，在SF膜上培养的cADMMSC中，软骨生成标记Sox9和Aggrecan的基因表达在统计学上显着上调。该结果表明，当细胞在没有特定培养条件的标准细胞培养基中的SF膜上生长时，可能会发生cADMMSC的软骨形成，以前认为这是诱导软骨分化的必要条件。与阴性对照cADMMSC相比，在SF膜上培养的cADMMSC中，软骨生成标记Sox9和Aggrecan的基因表达在统计学上显着上调。该结果表明，当细胞在没有特定培养条件的标准细胞培养基中的SF膜上生长时，可能会发生cADMMSC的软骨形成，以前认为这是诱导软骨分化的必要条件。