PATHOBIOLOGY OF GLOMERULAR MATRIX METABOLISM

这个项目的长期目标是更好地理解 控制肾小球结构和功能的因素 细胞外基质。这是一个高度专业化的结构， 负责维护肾小球滤过功能。 肾小球疾病经常与肾小球 肾小球基质的结构完整性或随积聚 这种材料的异常数量。肾小球系膜细胞 已经发现在培养基中分泌一种酶活性，这种酶可以 降解一种关键的基底膜成分--IV型胶原。这 纯化并鉴定了酶的活性，发现为IV型 胶原酶/明胶酶。广泛的结构分析表明，这 酶可能是唯一的，使用特定抗体进行初步实验 已将该酶定位于肾小球系膜或正常 肾炎动物。建议继续实施结构性改革 该酶的分子克隆和序列分析鉴定 并确定该酶在几种模型中的表达程度 肾炎的症状。这些表达研究将在 免疫组织化学和原位杂交新方法的应用 这是我们实验室研发的。最后，聚合酶链式反应将 被用来扩增相关金属蛋白酶的序列 正常动物和肾炎动物的肾小球，因此显著延长 我们目前对蛋白水解酶的类型和模式的了解 由固有的肾小球细胞表达。这类信息 可能会导致高度特异的抑制剂的开发 可用于阻断炎症性疾病中这些酶的过度活性 各州。

The long-term goals of this project concern a better understanding of the factors controlling the structure and function of the glomerular extracellular matrix. This is a highly specialized structure which is responsible for the maintenance of the glomerular filtration function. Diseases of the glomerulus are frequently associated with alterations in the structural integrity of the glomerular matrix or with the accumulation of abnormal quantities of this material. Glomerular mesangial cells have been found to secrete into culture medium an enzyme activity which can degrade a critical basement membrane component, type IV collagen. This enzyme activity was purified and characterized and found to be a type IV collagenase/gelatinase. Extensive structural analyses suggest that this enzyme may be unique and preliminary experiments using specific antibodies have localized this enzyme to the glomerular mesangium or normal and nephritianimals. It is proposed to continue the structural characterization of this enzyme by molecular cloning and sequence analysis and to determine the degree of expression of this enzyme in several models of nephritis. These expression studies will be performed at the immunohistochemical and in situ hybridization levels, using a new method developed in our laboratory. Finally, the polymerase chain reaction will be used to amplify sequences for related metalloproteases from the glomeruli of normal and nephritic animals, thereby considerably extending our current understanding of the types and patterns of proteolytic enzymes expressed by the intrinsic glomerular cells. This type of information could possibly lead to the development of highly specific inhibitors which could be used to block excessive activity of these enzymes in inflammatory states.