BIOSYNTHETIC HUMAN EGF ACTION ON CORNEAL WOUND HEALING

目前还没有有效的治疗方法来刺激愈合 由手术、创伤或疾病引起的基质内皮损伤， 然而角膜伤口的不充分愈合可导致严重的 并发症 我们的长期目标是了解 调节角膜自然愈合过程的机制， 并开发刺激角膜愈合的方法。 我们的假设 角膜的正常愈合是由肽的生长调节的 由损伤区域的细胞产生的因子。 这些肽 生长因子通过自分泌或旁分泌机制起作用， 刺激角膜细胞有丝分裂和迁移。 这一假设 这意味着角膜愈合不充分是由于 伤口刺激因子及其受体的产生或 创伤抑制因子及其受体的过度产生。 此外，这意味着添加适当的刺激肽， 生长因子将刺激角膜伤口的愈合。 测试 根据这一假设，我们建议分析牛和人的角膜 角膜细胞和内皮细胞产生8种mRNA 不同的生长因子（EGF，bFGF，aFGF，TGF-α，TGF-β， IGF-I、IGF-II、PDGF），使用cDNA杂交技术（斑点印迹， 北方，原位杂交）。 我们将确定 这些生长因子和EGF受体的变化， 伤口愈合的过程中，我们将调查什么生理 这些物质可以调节它们的表达水平。 另外我们 将研究EGF作用于角膜的分子机制， 通过生物化学表征细胞基质， 表皮生长因子受体激酶（EGF receptor kinase） 为了进一步测试 这一假设在体内，我们将测量角膜的强度， 局部用生物合成的bFGF、IGF- I、PDGF或TGF-β，我们将评估 含有生长因子的制剂对刺激有丝分裂的 猫角膜内皮 这些实验的结果应该 进一步加深了我们对分子机制的基本理解 调节角膜伤口愈合，并表明 外源性生长因子治疗的临床应用 刺激角膜愈合。

Currently there are no effective treatments for stimulating healing of stromal endothelial wounds caused by surgery, trauma or disease, yet inadequate healing of corneal wounds can lead to severe complications. Our long term goals are to understand the molecular mechanisms that regulate the natural healing process in the cornea, and to develop ways to stimulate corneal healing. Our hypothesis is that normal healing in the cornea is regulated by peptide growth factors produced by cells in the area of injury. These peptide growth factors operate via autocrine or paracrine mechanisms to stimulate mitosis and migration of corneal cells. This hypothesis implies that inadequate corneal healing results from insufficient production of wound stimulating factors and their receptors or the overproduction of wound inhibiting factors and their receptors. Also, it implies that addition of appropriate stimulating peptide growth factors would stimulate healing of corneal wounds. To test this hypothesis, we propose to analyze bovine and human corneal keratocytes and endothelial cells for production of mRNA for eight different growth factors (EGF, bFGF, aFGF, TGF-alpha, TGF-beta, IGF-I, IGF-II, PDGF) using cDNA hybridization techniques (dot-blot, Northern, in situ hybridization). We will determine if the levels of these growth factors and the EGF receptor change during the course of wound healing, and we will investigate what physiological substances may regulate the level of their expression. Also, we will investigate the molecular mechanism of EGF action on corneal cells by biochemically characterizing the cellular substrates which are phosphorylated by the EGF receptor kinase. To further test this hypothesis in vivo, we will measure the strength of corneal incisions in rabbits treated topically with biosynthetic bFGF, IGF- I, PDGF, or TGF-beta, and we will evaluate the effect of formulations containing growth factors on stimulating mitosis of cat corneal endothelium. Results from these experiments should further our basic understanding of the molecular mechanism regulating corneal wound healing, and indicate the potential clinical usefulness of exogenous growth factor therapy in stimulating corneal healing.