Stem-Cell Properties of Human Corneal Keratocytes

我寻求克格勃职业发展奖的目的有两个：1)考察 出生后的人类角质形成细胞和人类神经嵴干细胞在卵子中；2)发展我的职业生涯 通过实践研究经验、教学和指导，在干细胞生物学领域担任独立研究员。 人类角膜失明的最常见原因是视觉上显著的基质疤痕和 内皮细胞功能障碍。在美国，据预测，随着屈光手术的到来， 适合移植的供体角膜将大幅减少。由于这些挑战，有 对使用具有自我更新、分化为多细胞 细胞谱系和体内组织重建，用于治疗角膜疾病。虽然已经有了 最近有报道称，人的角膜干细胞可以被诱导表达与多基因一致的标志。 在细胞培养中的潜能，对分化的角膜基质细胞的多潜能知之甚少。我们的 初步数据显示，从出生后角膜分离的人角膜基质细胞具有 在鸡胚胎环境中分化为神经脊衍生物。这是第一个证据，尽管 早期，人类角质形成细胞和出生后(与胚胎相比)的角质形成细胞保留了 作为部分限制性前体细胞的神经脊前体细胞。在工作中 这一建议的假设是，人类出生后的角质形成细胞保持其神经脊的多能性。 神经前体细胞具有分化为神经脊衍生物的能力，包括其他眼组织。 此外，鸡胚胎微环境可能包含分化所需的足够信号。 人神经脊干细胞植入眼组织，以及其他神经脊来源的结构。三 将讨论具体目标；目标1；描述人类出生后角质形成细胞的多潜能， 以鸡胚胎环境为检测系统。目标2：检查年龄和 人角膜基质细胞多向分化的研究现状。目标3：探索人类的潜力 在卵子中神经脊干细胞形成神经脊眼部衍生品。 相关性(见说明)； 供体角膜的可获得性往往限制了治疗角膜疤痕的能力，角膜疤痕是第二常见的 导致全世界失明的原因。我们的目标是了解出生后人类角质形成细胞和 神经脊干细胞在胚胎环境中分化为眼组织。这将作为一种 为确定创造用于再生医学的专门细胞的可行性奠定了基础。

My objectives in seeking a KGB career development award are two-fold: 1) to examine the multipotentiality of post-natal human keratocytes and human neural crest stem cells in ovo and; 2) to develop my career as an independent investigator in stem cell biology by hands-on research experience, didactics and mentorship. The most common causes of human corneal blindness are visually significant stromal scarring and endothelial cell dysfunction. In the US, it is predicted that with the advent of refractive surgery, the supply of donor corneas suitable for transplantation will be significantly reduced. Because of these challenges, there is significant interest in pursuing the use of cells that have the ability to self-renew, differentiate into multiple cell lineages, and remodel tissues in vivo, in the treatment of corneal disorders. While there have been recent reports of human cornea stem cells that can be induced to express markers consistent with multi- potency in cell culture, little is known about the multi-potentiality of differentiated cornea stromal cells. Our preliminary data indicate that human keratocytes isolated from postnatal corneas have the ability to differentiate into neural crest derivatives in the chick embryonic environment. This is the first evidence, albeit early, that human keratocytes and postnatal (versus embryonic) keratocytes retain the multi-potentiality of the neural crest precursors from which they are derived as partially restricted progenitors. The working hypothesis of this proposal is that human postnatal keratocytes retain the multi-potency of their neural crest precursors and have the ability to differentiate into neural crest derivatives, including other ocular tissues. Further, the chick embryonic microenvironment likely contains the adequate signals required to differentiate human neural crest stem cells into ocular tissues, as well as other neural crest-derived structures. Three specific aims will be addressed; Aim 1; characterize the multipotentiality of human post-natal keratocytes, using the chick embryonic environment as an assay system. Aim 2: examine the effects of age and differentiation status on the multipotentiality of human keratocytes. Aim 3; explore the potential for human neural crest stem cells to form neural crest ocular derivatives in ovo. RELEVANCE (See instructions); The availability of donor corneas often limits the ability to treat corneal scarring, the second most common cause of blindness worldwide. Our goal is to understand the ability of post-natal human keratocytes and neural crest stem cells to differentiate into ocular tissues in an embryonic environment. This will serve as a basis for determining the feasibility of creating specialized cells for use in regenerative medicine.