Ji Lin, Allen-Hoffmann B Lynn, de Pablo Juan J, Palecek Sean P
Department of Chemical and Biological Engineering, University of Wisconsin-Madison, 53706, USA.
Tissue Eng. 2006 Apr;12(4):665-79. doi: 10.1089/ten.2006.12.665.
Human embryonic stem cells (hESC) hold tremendous potential in the future of tissue engineering, offering promise as a source of virtually unlimited quantities of desired cell and tissue types. We have identified soluble chemical and extracellular matrix factors that permit isolation of keratinocyte precursors from hESCs. Culturing embryoid bodies (EB) formed from hESCs in a defined serum-free keratinocyte growth medium on a gelatin matrix generated keratin 14 (K14) expressing cells with an epithelial morphology. These K14 expressing cells could be subcultured in medium supplemented with hydrocortisone and induced to stratify and terminally differentiate by addition of calcium. Optimum times for obtaining K14 expressing cells were found for EB formation and for differentiation and growth of cultures after EB plating. EB formation was not necessary to generate keratinocyte precursors; direct transfer of hESC colonies to keratinocyte growth medium permitted differentiation into the keratinocyte lineage. With further studies to optimize generation and purification of hESC-derived keratinocyte precursors, these cells could provide a source of epidermal cells for skin tissue engineering applications in vitro or in vivo.
人类胚胎干细胞（hESC）在组织工程的未来具有巨大潜力，有望成为几乎无限量所需细胞和组织类型的来源。我们已经鉴定出可溶性化学和细胞外基质因子，这些因子可用于从hESC中分离角质形成细胞前体。在明胶基质上的特定无血清角质形成细胞生长培养基中培养由hESC形成的胚状体（EB），可产生具有上皮形态且表达角蛋白14（K14）的细胞。这些表达K14的细胞可以在添加了氢化可的松的培养基中传代培养，并通过添加钙诱导分层和终末分化。确定了形成EB以及EB接种后培养物分化和生长以获得表达K14细胞的最佳时间。生成角质形成细胞前体并不一定需要形成EB；将hESC集落直接转移到角质形成细胞生长培养基中可使其分化为角质形成细胞谱系。随着进一步研究以优化hESC来源的角质形成细胞前体的生成和纯化，这些细胞可为体外或体内皮肤组织工程应用提供表皮细胞来源。
