Mathews Smitha, Mathew Suja Ann, Gupta Pawan Kumar, Bhonde Ramesh, Totey Satish
Manipal Institute of Regenerative Medicine, Manipal University, 10 Service Road, Domlur, Bangalore-560071, India.
J Tissue Eng Regen Med. 2014 Feb;8(2):143-52. doi: 10.1002/term.1507. Epub 2012 Apr 12.
Extracellular matrix plays an important role in regulating cell growth and differentiation. The biomimetic approach of cell-based tissue engineering is based on mirroring this in vivo micro environment for developing a functional tissue engineered construct. In this study, we treated normal tissue culture plates with selected extracellular matrix components consisting of glycosaminoglycans such as chondroitin-4-sulphate, dermatan sulphate, chondroitin-6-sulphate, heparin and hyaluronic acid. Mesenchymal stem cells isolated from adult human bone marrow were cultured on the glycosaminoglycan treated culture plates to evaluate their regulatory role in cell growth and osteoblast differentiation. Although no significant improvement on human mesenchymal stem cell adhesion and proliferation was observed on the glycosaminoglycan-treated tissue culture plates, there was selective osteoblast differentiation, indicating its potential role in differentiation rather than proliferation. Osteoblast differentiation studies showed high osteogenic potential for all tested glycosaminoglycans except chondroitin-4-sulphate. Osteoblast differentiation-associated genes such as osterix, osteocalcin, integrin binding sialoprotein, osteonectin and collagen, type 1, alpha 1 showed significant upregulation. We identified osterix as the key transcription factor responsible for the enhanced bone matrix deposition observed on hyaluronic acid, heparin and chondroitin-6-sulphate. Hyaluronic acid provided the most favourable condition for osteoblast differentiation and bone matrix synthesis. Our results confirm and emphasise the significant role of extracellular matrix in regulating cell differentiation. To summarise, glycosaminoglycans of extracellular matrix played a significant role in regulating osteoblast differentiation and could be exploited in the biomimetic approach of fabricating or functionalizing scaffolds for stem cell based bone tissue engineering.
细胞外基质在调节细胞生长和分化中发挥着重要作用。基于细胞的组织工程的仿生方法是基于模拟这种体内微环境来开发功能性组织工程构建体。在本研究中，我们用选定的细胞外基质成分处理正常组织培养板，这些成分包括硫酸软骨素 - 4、硫酸皮肤素、硫酸软骨素 - 6、肝素和透明质酸等糖胺聚糖。从成人骨髓中分离的间充质干细胞在经糖胺聚糖处理的培养板上培养，以评估它们在细胞生长和成骨细胞分化中的调节作用。尽管在经糖胺聚糖处理的组织培养板上未观察到人间充质干细胞黏附和增殖有显著改善，但存在选择性成骨细胞分化，表明其在分化而非增殖中的潜在作用。成骨细胞分化研究表明，除硫酸软骨素 - 4外，所有测试的糖胺聚糖都具有高成骨潜力。成骨细胞分化相关基因，如osterix、骨钙素、整合素结合涎蛋白、骨连接蛋白和I型胶原α1，均显示出显著上调。我们确定osterix是负责在透明质酸、肝素和硫酸软骨素 - 6上观察到的骨基质沉积增强的关键转录因子。透明质酸为成骨细胞分化和骨基质合成提供了最有利的条件。我们的结果证实并强调了细胞外基质在调节细胞分化中的重要作用。总之，细胞外基质的糖胺聚糖在调节成骨细胞分化中发挥了重要作用，可用于基于干细胞的骨组织工程支架制造或功能化的仿生方法中。
