Department of Ophthalmology, University of Washington, Seattle, Washington, USA.
Stem Cells Dev. 2013 Aug 1;22(15):2186-95. doi: 10.1089/scd.2013.0011. Epub 2013 Apr 5.
The human cornea contains stem cells that can be induced to express markers consistent with multipotency in cell culture; however, there have been no studies demonstrating that human corneal keratocytes are multipotent. The objective of this study is to examine the potential of human fetal keratocytes (HFKs) to differentiate into neural crest-derived tissues when challenged in an embryonic environment. HFKs were injected bilaterally into the cranial mesenchyme adjacent to the neural tube and the periocular mesenchyme in chick embryos at embryonic days 1.5 and 3, respectively. The injected keratocytes were detected by immunofluorescence using the human cell-specific marker, HuNu. HuNu-positive keratocytes injected along the neural crest pathway were localized adjacent to HNK-1-positive migratory host neural crest cells and in the cardiac cushion mesenchyme. The HuNu-positive cells transformed into neural crest derivatives such as smooth muscle in cranial blood vessels, stromal keratocytes, and corneal endothelium. However, they failed to form neurons despite their presence in the condensing trigeminal ganglion. These results show that HFKs retain the ability to differentiate into some neural crest-derived tissues. Their ability to respond to embryonic cues and generate corneal endothelium and stromal keratocytes provides a basis for understanding the feasibility of creating specialized cells for possible use in regenerative medicine.
人眼角膜包含干细胞，这些干细胞在细胞培养中可以被诱导表达多能性标志物；然而，目前还没有研究表明人角膜成纤维细胞具有多能性。本研究的目的是研究人胎儿角膜成纤维细胞（HFKs）在胚胎环境中受到挑战时分化为神经嵴来源组织的潜力。将 HFKs 分别在鸡胚 1.5 天和 3 天双侧注射到神经管附近的颅间质和眼眶间质中。使用人细胞特异性标志物 HuNu 通过免疫荧光检测注射的角膜成纤维细胞。沿神经嵴途径注射的 HuNu 阳性角膜成纤维细胞定位于 HNK-1 阳性迁移的宿主神经嵴细胞和心垫间质附近。HuNu 阳性细胞转化为神经嵴衍生物，如颅血管中的平滑肌、基质角膜成纤维细胞和角膜内皮细胞。然而，尽管它们存在于正在形成的三叉神经节中，它们未能形成神经元。这些结果表明 HFKs 保留了分化为一些神经嵴来源组织的能力。它们对胚胎信号的反应能力以及产生角膜内皮细胞和基质角膜成纤维细胞的能力为理解为可能用于再生医学而创建专门细胞的可行性提供了基础。
