Gene Discovery in Mouse Models for Secondary Cataracts

描述（由申请人提供）：上皮细胞向间充质细胞转化（EMT）是白内障手术后的主要问题之一。附着在晶状体囊上的晶状体上皮细胞可以生长并分化为间充质细胞，导致后囊膜混浊（PCO）。这个过程会导致继发性白内障，需要再次治疗。鉴定促进晶状体上皮细胞转分化的因素对白内障的治疗至关重要。不幸的是，这一领域的实验受到缺乏实验模型的阻碍，而这些模型可以应用强大的遗传技术。我们发现，当对小鼠进行囊外手术时，囊上剩余的晶状体上皮细胞迅速增殖，并使囊内充满看起来正常的晶状体纤维。“再生”晶状体的正常形态也可以看到，有既定的弓形区域。再生晶状体的形态取决于手术和晶状体囊的完整性。然而，晶状体上皮细胞在向晶状体纤维正常分化的同时，也可以转分化为间充质细胞，尤其是在晶状体再生的早期。因此，该小鼠晶状体再生模型可以成为研究PCO不可缺少的和长期寻求的动物模型。利用这样一个动物模型系统，我们建议在此过程中研究全局基因表达模式和基因发现。为了实现这一目标，我们将研究具有EMT和PCO重要基因突变的小鼠的晶状体再生。同时，这些小鼠进行晶状体再生或EMT的能力将与全小鼠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荚膜袋的功能分析中得到验证。将建立的数据库将相互比较，并与从发育、成人和白内障晶体建立的数据库进行比较。这项研究将最终确定参与EMT和PCO以及正常晶状体纤维分化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后囊膜混浊的消除开辟新的途径。此外，本研究将探讨晶状体上皮细胞进行EMT的双性性，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.