Ocular Stem Cells for Vision Recovery

描述（由申请人提供）：候选人是一名医学博士/博士培训的眼科医生和眼科整形外科医生，其职业目标是研究干细胞及其在治疗眼部和眼眶疾病中的应用。职业发展计划将由Ihor Lemishcka博士和Mario Wolosin博士共同指导。他们的实验室分别专注于人类胚胎和诱导多能干细胞生物学以及角膜缘干细胞。候选人的长期目标是了解是什么控制干细胞分化为不同的眼部和眼眶组织，目的是创造用于移植的自体组织。全世界有超过600万人因眼表损伤而失明。烧伤、创伤、感染、遗传性疾病和慢性炎症导致角膜缘上皮干细胞缺陷（LSCD）和由角膜瘢痕形成、血管形成和结膜形成引起的持续性视力丧失。角膜缘干细胞的替代通常需要恢复视力。在单侧LSCD病例中，对侧眼是一个明显的自体细胞来源;在双侧LSCD患者中（在双侧失明的情况下），角膜缘同种异体移植是唯一的选择。由于尚不完全清楚的原因，这些患者尽管使用免疫抑制剂，但同种异体移植物通常在几年内失败。因此，自体细胞是恢复持久视力所必需的。我们建议开发一种方案来产生能够在体内获得角膜表型的自体诱导多能干细胞（iPSC）衍生的细胞。我们的目标是（1）从胚胎学起源更接近角膜缘-角膜谱系的细胞产生iPSC，所述角膜缘-角膜谱系包括人眼睑皮肤和结膜皮肤。 和颊上皮细胞，（2）使用外胚层分化方案结合可溶性因子和角膜缘小生境培养通过祖细胞分化iPSC，和（3）使用建立的人组织进入兔模型评估所产生的细胞用于眼表面再生的能力。该提案的资金将促进眼表疾病新干细胞疗法的发现，并使再生医学成为失明患者的现实。

DESCRIPTION (provided by applicant): The candidate is an MD/PhD trained ophthalmologist and ophthalmic plastic surgeon with the career goal of studying stem cells and their application to cure ocular and orbital disease. The career development plan will be jointly mentored by Drs. Ihor Lemishcka and Mario Wolosin. Their laboratories focus of human embryonic and induced pluripotent stem cell biology and corneal limbal stem cells, respectively. The candidate's long-term aim is to understand what controls stem cell differentiation into distinct ocular and orbital tissues, with the goal of creating autologous tissue for transplantation. Over 6 million people worldwide are blind from damage to the ocular surface. Burns, trauma, infection, genetic diseases, and chronic inflammation result in limbal epithelial stem cell deficiency (LSCD) and persistent vision loss from corneal scarring, vascularization and conjunctivalization. Replacement of limbal stem cells is often required to restore vision. In unilateral LSCD cases, the fellow eye is an obvious autologous cell source; in patients with bilateral LSCD (in cases of bilateral blindness) limbal allografts are the only option. For reasons not fully understood, allografts often fail within a few years in these patients despite immunosuppression. Thus, autologous cells are necessary to restore lasting vision. We propose to develop a protocol to generate autologous induced pluripotent stem cell (iPSC)-derived cells capable of acquiring the corneal phenotype in vivo. Our aims are to (1) generate iPSC from cells whose embryological origin is closer to the limbal- corneal lineage, which includes human eyelid skin, and conjunctival and buccal epithelia, (2) differentiate iPSC via progenitor cells using an ectodermal differentiation protocol in combination with soluble factors and limbal niche culture, and (3) assess the ability of the generated cells for ocular surface regeneration using an established human tissue into rabbit model. The funding for this proposal will facilitate the discovery of new stem cell therapies for ocular surface disease and make regenerative medicine a reality for those burdened with blindness.