Gene Discovery in Mouse Models for Secondary Cataracts

描述(申请人提供)：上皮细胞到间充质细胞的转变(EMT)是白内障手术后的主要问题之一。晶状体上皮细胞附着在晶状体囊膜上，可生长分化为间充质细胞，导致后囊混浊。这一过程导致了必须再次治疗的继发性白内障。识别促进晶状体上皮细胞转分化的因素对于后囊混浊的可能治疗至关重要。不幸的是，由于缺乏可以应用强大基因技术的实验模型，这一领域的实验受到阻碍。我们发现，当对小鼠进行囊外手术时，囊膜上剩余的晶状体上皮细胞迅速增殖，并用看起来正常的晶状体纤维填充囊袋。正常形态的“再生”晶状体也可以看到，并建立了弓形区域。晶状体再生的形态取决于手术和晶状体囊的完整性。然而，随着晶状体纤维的正常分化，晶状体上皮细胞也可以转分化为间充质细胞，尤其是在晶状体再生的早期阶段。因此，这种晶状体再生的小鼠模型可以成为研究PCO不可或缺的和长期寻找的动物模型。利用这样的动物模型系统，我们建议在这个过程中研究全球基因表达模式和基因发现。为了实现这一点，我们将检查具有EMT和PCO重要基因突变的小鼠的晶状体再生。同时，这些小鼠接受(或不经历)晶状体再生或EMT的能力将与使用小鼠全基因组微阵列的基因表达相关。关键基因的表达和作用将在使用胶囊袋进行的功能分析中得到验证。将建立的数据库将相互比较，并与正在发育的晶状体、成人晶状体和白内障晶状体建立的数据库进行比较。这项研究最终将确定与EMT和PCO以及正常晶状体纤维分化有关的已知和新基因的基因模式。本研究旨在为继发性白内障的治疗和消除后囊混浊开辟新的途径。此外，这项研究还将探讨晶状体上皮细胞接受EMT的双能性，这会导致继发性白内障，或晶状体纤维分化，这是一个正常的修复过程。

DESCRIPTION (provided by applicant): Epithelial to Mesenchymal Cell Transition (EMT) is one of the major problems following cataract surgery. Lens epithelial cells adherent to the lens capsule can grow and differentiate into mesenchymal cells resulting in posterior capsule opacification (PCO). This process leads to secondary cataracts that have to be treated again. Identification of factors that promote transdifferentiation of the lens epithelial cells is of paramount importance for possible therapies of PCO. Unfortunately, experiments in this field are hindered by the lack of experimental models where the powerful genetic techniques can be applied. We have found that when extracapsular surgery is performed in the mouse, the remaining lens epithelial cells on the capsule proliferate rapidly and fill the bag with normal looking lens fibers. Normal morphology of the "regenerated" lens can also be seen, with established bow regions. The morphology of the regenerated lens depends on the surgery and the integrity of the lens capsule. However, along with the normal differentiation to lens fibers, lens epithelial cells can also transdifferentiate to mesenchymal cells, especially at the early stages of lens regeneration. This lens regeneration mouse model can become, therefore, an indispensable and long-sought animal model to study PCO. Taking advantage of such an animal model system we propose to study global gene expression patterns and gene discovery during the process. In order to achieve this we will examine lens regeneration in mice with mutations in genes important to EMT and PCO. At the same time the ability of these mice to undergo (or not) lens regeneration or EMT will be correlated with gene expression using whole mouse genome microarrays. Expression and roles of key genes will be verified in functional assays using capsular bags. The databases that will be established will be compared with each other and with databases established from developing, adult and cataractous lenses. This research will eventually identify gene patterns of known and novel genes that are involved in EMT and PCO as well as in normal lens fiber differentiation. This research aims to establish new ways for the treatment of secondary cataracts and the elimination of posterior capsule opacification. Also, this research will address the bipotency of lens epithelial cells to undergo EMT, which results in secondary cataracts, or lens fiber differentiation, which is a normal repair process.