The Influence of Capsule Composition on Lens Biology

描述(申请人提供)：晶状体囊膜是一种无细胞的增厚基底膜，从晶状体最早的发育阶段到死亡都完全包裹在晶状体周围。大量研究表明，晶状体囊膜对晶状体的发育和功能是必不可少的，许多人类和动物疾病会导致晶状体囊膜异常，经常导致视力退化或破坏。最近，我们证明了IV型胶原网络的组成在晶状体发育过程中发生了变化，因此与基底膜弹性相关的IV型胶原在发育早期就表达了，而与基底膜强度相关的IV型胶原直到睁开眼睑后才表达。这导致了一种假设，即晶状体囊膜成分的表达在发育过程中发生变化，以允许胚胎发育期间晶状体囊膜面积增加200倍，并提供调节所需的强度。这一假设将通过使用转基因小鼠方法改变晶状体的IV型胶原亚型组成来检验。由于至少有一类基膜分子是在晶状体发育过程中差异合成的，我们假设其他基膜分子也会有类似的表达谱，这也可能对晶状体功能产生重大影响。因此，我们先前的微阵列分析发现在晶状体中表达的细胞外基质分子的发育表达模式也将被确定。晶状体囊膜中IV型胶原亚型组成的变化和其他细胞外基质分子的存在在晶状体生物学中所起的作用将通过在有或没有基质成分的情况下对原代培养的小鼠晶状体上皮细胞或新鲜分离的牛晶状体上皮细胞进行细胞黏附、迁移和增殖分析来测试。这些研究既将阐明晶状体囊的分子组成，又将阐述晶状体囊在附着的晶状体细胞的生物学中所起的作用。

DESCRIPTION (provided by applicant): The lens capsule is an acellular, thickened basement membrane that completely surrounds the lens from its earliest developmental stages until death. Numerous studies have shown that the capsule is essential for lens development and function and a number of human and animal diseases result in lens capsule abnormalities, often leading to the degradation or destruction of vision. Recently, we demonstrated that the composition of the collagen IV network changes during lens development so that the collagen IV subtypes associated with basement membrane elasticity are expressed during early development while those associated with basement membrane strength are not expressed until after eye lid opening. This led to the hypothesis that the expression of lens capsule components changes during development to allow for both the 200 fold increase in capsule area during embryogenesis and the strength necessary for accomodation. This hypothesis will be tested by changing the collagen IV subtype composition of the lens using transgenic mouse approaches. Since at least one class of basement membrane molecules is differentially synthesized during lens development, we hypothesize that other basement membrane molecules will have similar expression profiles which could also have dramatic consequences on lens function. Thus, the developmental expression pattern of extracellular matrix molecules found to be expressed in the lens by our prior microarray analyses will be determined as well. The role that both the changing collagen IV subtype composition and the presence of other extracellular matrix molecules in the lens capsule plays in lens biology will be tested by cell adhesion, migration and proliferation assays on either primary cultures of mouse lens epithelial cells or freshly isolated bovine lens epithelial cells in the presence or absence of matrix components. These studies will both elucidate the molecular composition of the lens capsule and address the role that the capsule plays in the biology of the attached lens cells.