Gauthaman Kalamegam, Fong Chui-Yee, Venugopal Jayarama Reddy, Biswas Arijit, Ramakrishna Seeram, Bongso Ariff
Department of Obstetrics and Gynecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
Methods Mol Biol. 2013;1058:1-23. doi: 10.1007/7651_2012_1.
Stem cells isolated from the Wharton's jelly of the human umbilical cord (hWJSCs) are unique compared to other stem cell types as they lie in between embryonic stem cells (ESCs) and adult mesenchymal stem cells (MSCs) on the developmental map and share stemness markers of ESCs and MSCs. Yet, they do not induce tumorigenesis and are hypoimmunogenic and proliferative and fresh cell numbers can be harvested painlessly in abundance from discarded umbilical cords. Additionally, they secrete important soluble bioactive molecules from the interleukin and cell adhesion family, hyaluronic acid, collagen, glycosoaminoglycans, and chondroitin sulfate. Many of these molecules are involved in bone, cartilage, and joint repair. It has also been shown that hWJSCs attach, proliferate, and differentiate efficiently in the stem cell niches of three-dimensional matrices, particularly nanofibrous scaffolds. Thus, tissue constructs made up of hWJSCs and biodegradable nanofibrous scaffolds will facilitate clinical translation and improved functional outcome for arthritis, bone, and cartilage diseases. When applied in vivo, the hWJSCs from the tissue construct may improve repair either by differentiating into new chondrocytes or osteocytes and/or release of important factors that favor repair through paracrine functions. The nanofibrous scaffold is expected to provide the architecture and niches for the hWJSCs to perform and will later biodegrade encouraging engraftment. This chapter provides a step-by-step protocol for the preparation of such tissue constructs involving hWJSCs and nanofibrous scaffolds. The methodology also includes the targeted in vitro differentiation of the hWJSCs to osteogenic and chondrogenic lineages when attached to the nanofibrous scaffolds.
从人脐带华通氏胶中分离出的干细胞（hWJSCs）与其他类型的干细胞相比具有独特性，因为在发育图谱上，它们介于胚胎干细胞（ESCs）和成人间充质干细胞（MSCs）之间，并共享ESCs和MSCs的干性标志物。然而，它们不会诱发肿瘤形成，具有低免疫原性且增殖能力强，并且可以从废弃的脐带中无痛大量收获新鲜细胞。此外，它们能分泌来自白细胞介素和细胞粘附家族、透明质酸、胶原蛋白、糖胺聚糖和硫酸软骨素等重要的可溶性生物活性分子。这些分子中的许多都参与骨骼、软骨和关节修复。研究还表明，hWJSCs能在三维基质，特别是纳米纤维支架的干细胞微环境中有效附着、增殖和分化。因此，由hWJSCs和可生物降解的纳米纤维支架组成的组织构建体将促进关节炎、骨骼和软骨疾病的临床转化并改善功能结果。当在体内应用时，组织构建体中的hWJSCs可能通过分化为新的软骨细胞或骨细胞和/或通过旁分泌功能释放有利于修复的重要因子来改善修复。纳米纤维支架有望为hWJSCs发挥作用提供结构和微环境，并且随后会生物降解以促进植入。本章提供了一个涉及hWJSCs和纳米纤维支架的此类组织构建体制备的分步方案。该方法还包括当hWJSCs附着于纳米纤维支架时，将其定向体外分化为成骨和成软骨谱系。
