Surgical Rehabilitation of Ocular Surface : Epithelial Transplantation

我们的目标是开发原发性眼表疾病的有效治疗方法。为此，在本项目中，我们主要研究控制角膜上皮细胞增殖和分化的方法。首先，建立了兔角膜上皮细胞冷冻和长期传代培养的贵族细胞培养体系。该培养基由极低的Ca^<2+>浓度和高的氨基酸含量组成。其次，建立永生化兔角膜上皮细胞系。为此，用重组sv40腺病毒载体感染原代培养的兔角膜上皮细胞并克隆。该细胞系具有与正常角膜上皮细胞一致的特性。虽然这些细胞目前还不能作为上皮移植进行转移，但我们的成功在体外处理角膜上皮细胞方面取得了显著进展。第三，我们研究了几种细胞生长和/或调节因子的生物学作用。例如，主要来自泪腺的表皮生长因子促进了角膜上皮细胞的生长。在角质细胞生长因子中也发现了类似的现象，但这只在角膜基质细胞中产生。另一方面，转化生长因子- β对角膜上皮细胞生长有抑制作用。我们还研究了三种TGF- β亚型在角膜中的部分分布，发现TGF- β 2占主导地位。在体内同种异体上皮移植排斥反应的研究中，我们正在研究角膜上皮移植后接受环孢素治疗的患者泪液中IL-2的水平。

We aimed at developing effective treatment for primary ocular surface disorders. For this, in this project, we mainly focused on the methods controlling proliferation and differentiation of corneal epithelial cells. First, we established a noble cell culture system for freeze and long-term subculture of rabbit corneal epithelial cells. This culture media is composed of very low Ca^<2+> concentration with high aminoacid contents. Second, we established an immortalized rabbit corneal epithelial cell line. For this, primary cultured rabbit corneal epithelial cells were infected with a recombinant SV40-adenovirus vector and were cloned. This cell line shares properties consistent with normal corneal epithelial cells. Although these cells were not transferable as a epithelial transplantation at this point, our success has made a marked progress in handling corneal epithelial cells in vitro. Third, we investigated biological roles of several cell growth and/or regulatory factors. For instance, epidermal growth factor, which mainly comes from lacrimal gland, promoted corneal epithelial cell growth. Similar phenomenon was found in keratinocyte growth factor, but this was produced only in the corneal stromal cells. On the other hand, transforming growth factor -beta did inhibit corneal epithelial cell growth. We also studied spartial distribution of three TGF-beta isoforms in the cornea, and found TGF- beta 2 predominantly.In the study of epithelial allograft rejection in vivo, we are now investigating IL-2 levels in tears in patients with cyclosporin treatment after corneal epithelial transplantation.