Corneal endothelial cell survival in human donor corneas for transplantation

摘要 角膜内皮(CE)细胞丢失是角膜移植失败的关键危险因素 移植物的生命周期，可能最晚在最初成功后5-10年 移植。一种新的手术方法--Descemet剥离式自动内皮角膜移植 (DSAEK)在许多方面优于传统技术，需要 过度操纵角膜内皮，导致广泛的CE细胞丢失。 因此，接受过DSAEK治疗的患者未来可能发生晚期CE衰竭。 此前，我们已经报道了一种CE自分泌营养因子，即28个氨基酸 血管活性肠肽(VIP)维持角膜的分化状态 人供体内皮细胞的原位研究，包括CE细胞的大小、形状和滞留 外源性VIP可保护角膜免受氧化应激的杀伤作用。 血管活性肠肽增加CE细胞分化标记物N-钙粘蛋白的合成 黏附分子和抗细胞凋亡蛋白Bcl2的表达。中国的内生性VIP 睫状神经营养因子(CNTF)对CE细胞有上调作用，也是一种CE 在氧化应激中存活的CE细胞释放的自分泌营养因子。中国国家运输安全委员会 受体(CNTFR)在人供体角膜CE细胞中表达，并逐渐 在储存角膜的过程中丢失。通过应用从学习中获得的知识 CE细胞生理学对提高角膜移植CE细胞存活率的作用 这是我们的目标，我们也将验证这一知识的相关性。我们的特定 目的是要证明 1.新鲜人体供体角膜保存前的VIP处理增加 他们的CE细胞N-钙粘蛋白、Bcl-2、CNTFR和角膜储存中的滞留水平， 2.在人的微角膜刀切割时再进行一次VIP治疗 为DSAEK保存的供体角膜带来了AIM中描述的有益效果 1，减少DSAEK预切角膜CE细胞的凋亡和损伤， 3.新鲜人体供体角膜保存前的VIP处理和 在微角膜切割术前为DSAEK提供优质的预切角膜 已建立的体外内皮细胞损伤减少 角膜移植模型， 4.术中VIP(或CNTF)治疗可减少已建立的 体外内皮细胞角膜移植模型。

Abstract Corneal endothelial (CE) cell loss is a critical risk factor in corneal graft failure at any time in the life of the graft, which can be as late as 5-10 years after an initially successful transplant. A new procedure, Descemet's stripping automated endothelial keratoplasty (DSAEK), which is superior to the traditional technique in many aspects, requires extensive manipulation of the corneal endothelium, resulting in extensive CE cell loss. Thus, future development of late CE failure in eyes that have received DSAEK is likely. Previously, We have reported how a CE autocrine trophic factor, the 28 amino-acid vasoactive intestinal peptide (VIP) maintains the differentiated state of the corneal endothelium, including CE cell size, shape, and retention, in situ in the human donor cornea, whereas exogenous VIP protects it against the killing effect of oxidative stress. VIP increases synthesis of the CE cell differentiation marker N-cadherin, the cell-cell adhesion molecule, and that of the anti-apoptotic protein Bcl-2. The endogenous VIP in CE cells is upregulated by ciliary neurotrophic factor (CNTF), which is also a CE autocrine trophic factor released by CE cells surviving the oxidative stress. The CNTF receptor (CNTFR¿) is expressed in CE cells in human donor cornea and gradually becomes lost during corneal storage. By applying this knowledge gained from studying CE cell physiology to the enhancement of CE cell survival in corneal transplantation, which is our goal, we will also validate the relevance of this knowledge. Our specific aims are to demonstrate that 1. VIP treatment prior to storage of freshly dissected human donor corneas increases their CE cell N-cadherin, Bcl-2, CNTFR¿, and retention levels in corneal storage, 2. One additional VIP treatment at the time of microkeratome cutting of the human donor corneas stored for DSAEK brings about beneficial effects described in aim 1 and decreased CE cell apoptosis and injury to precut corneas for DSAEK, 3. VIP treatments prior to storage of freshly dissected human donor corneas and prior to microkeratome cutting produce superior precut corneas for DSAEK demonstrating decreased CE damage in an established in vitro endothelial keratoplasty model, 4. Intra-operative VIP (or CNTF) treatment decreases CE damage in an established in vitro endothelial keratoplasty model.