Meprins-Metalloproteinases of the Kidney and Intestine

Meprins-肾脏和肠道金属蛋白酶

• 批准号: 7920715
• 负责人: JUDITH S BOND
• 金额: $ 12.31万
• 依托单位: PENNSYLVANIA STATE UNIV HERSHEY MED CTR
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-21 至 2011-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7920715
• 关键词: Acute; Affect; Apical; Apoptotic; Bacteria; Bacterial Pili; Basement membrane; Binding; Bladder; Bone Marrow Cells; Cell Death; Cell Survival; Cell surface; Cells; Cleaved cell; Complex; Cyclic AMP-Dependent Protein Kinases; Cytosol; Defensins; Diagnosis; Disease; Epidermal Growth Factor Receptor; Epithelial Cells; Epitopes; Fibronectins; Functional disorder; Funding; Genotype; Green Fluorescent Proteins; Health; Host Defense; Hydrolysis; Hypoxia; Immunoprecipitation; Infection; Inflammatory; Injury; Intervention; Intestines; Ion Channel Protein; Ischemia; Kidney; Knockout Mice; Knowledge; Lead; Leukocytes; Location; MDCK cell; Mass Spectrum Analysis; Membrane; Meprin; Metalloproteases; Molecular; Morbidity - disease rate; Movement; Mus; Necrosis; Nidogen; Pathogenesis; Peptide Hydrolases; Peptide antibodies; Peptides; Predisposition; Prevention; Protein Isoforms; Proteins; Proteomics; Proximal Kidney Tubules; Radiation; Recombinants; Renal tubule structure; Reperfusion Injury; Reperfusion Therapy; Research; Resources; Role; Severities; Site; Source; Techniques; Tissues; Transfection; Urinary tract infection; Urologic Diseases; Work; apical membrane; beta-Defensins; brush border membrane; cytokine; extracellular; insight; irradiation; kidney cell; kidney epithelial cell; kidney infection; meprin alpha; prevent; research study; response

DESCRIPTION (provided by applicant): The overall long-term objectives of this research are to elucidate mechanisms by which cell surface metalloproteinases and their secreted counterparts are regulated and interact, activate and degrade peptides and proteins at the cell surface and extracellularly, as well as to define the roles of these proteases in health and diseases such as kidney and urinary tract disease. The work has led to the discovery and characterization of meprins, complex and unique mammalian metalloproteinases abundantly expressed at the brush border membrane of kidney and intestinal epithelial cells, and in leukocytes under certain conditions. The hypothesis is that meprins have a protective role in host defense in urinary tract infections, but that the alpha/beta form is actively involved in the pathophysiology of acute renal injury. In the next period, the Specific Aims are to: (1) Determine whether meprin alpha/beta is damaging to specific proteins in kidney epithelial cells in response to hypoxia or ischemia-reperfusion. Immunohistochemical, immunoprecipitation, and proteomic techniques will be used with kidneys and proximal tubules from wild-type and meprin knockout mice to identify specific targets of meprin interaction and hydrolysis in brush border membrane, cytosol and extracellular compartments. (2) Determine whether leukocytic meprins affect movement and activity of these inflammatory cells to ischemic kidney and enhance damage. Bone marrow cells from wild-type and meprin knockout mice will be destroyed by radiation, and replaced by donor leukocytes from wild-type or meprin knockout mice carrying a green- fluorescent protein. The movement of the donor leukocytes to kidneys in the chimeric mice subjected to ischemia-reperfusion, and the injury caused by meprin positive and negative leukocytes will give insight into the damage caused by these cells. (3) Determine whether meprin alpha secreted from the kidney, or leukocytic meprins, affect the establishment and severity of urinary tract disease. Mice of different meprin genotypes will be infected with uropathic bacteria in the bladder, and the susceptibility to bladder and kidney infections will be determined. The roles of leukocytic and kidney meprins will be assessed using the chimeric mice. The activation of meprins at sites of infection, concentrations of active beta-defensins, and interactions of meprin isoforms with bacteria will be assessed to gain insights into mechanisms of protection. The availability of the meprin alpha and beta knockout mice are unique resources for these studies, and fundamental knowledge of these metalloproteinases will lead to new concepts, treatments, and interventions for kidney and urinary tract diseases.

描述（由申请人提供）：本研究的总体长期目标是阐明细胞表面金属蛋白酶及其分泌型对应物在细胞表面和细胞外调节、相互作用、活化和降解肽和蛋白质的机制，以及确定这些蛋白酶在健康和疾病（如肾脏和尿路疾病）中的作用。这项工作导致了meprins的发现和表征，meprins是一种复杂而独特的哺乳动物金属蛋白酶，在肾脏和肠上皮细胞的刷状缘膜以及某些条件下的白细胞中大量表达。该假说认为，meprins在尿路感染的宿主防御中具有保护作用，但α/β形式积极参与急性肾损伤的病理生理学。在接下来的时间里，具体的目标是：（1）确定meprin α/β是否对缺氧或缺血-再灌注反应中的肾上皮细胞中的特定蛋白质造成损伤。免疫组织化学、免疫沉淀和蛋白质组学技术将用于野生型和meprin基因敲除小鼠的肾脏和近端小管，以鉴定meprin相互作用的特异性靶点以及刷状缘膜、细胞质和细胞外隔室中的水解。(2)确定白细胞膜是否影响这些炎性细胞对缺血肾脏的运动和活性，并增强损害。来自野生型和meprin敲除小鼠的骨髓细胞将被辐射破坏，并被来自携带绿色荧光蛋白的野生型或meprin敲除小鼠的供体白细胞取代。供体白细胞向缺血再灌注小鼠肾脏的迁移以及meprin阳性和阴性白细胞引起的损伤将使我们了解这些细胞引起的损伤。(3)确定是否meprin α分泌的肾脏，或白细胞meprin，影响建立和严重程度的尿路疾病。不同meprin基因型的小鼠将被膀胱中的尿路细菌感染，并且将确定对膀胱和肾脏感染的易感性。将使用嵌合小鼠评估白细胞和肾meprins的作用。将评估感染部位meprin的激活、活性β-防御素的浓度以及meprin同种型与细菌的相互作用，以深入了解保护机制。meprin α和β基因敲除小鼠的可用性是这些研究的独特资源，这些金属蛋白酶的基础知识将导致肾脏和尿路疾病的新概念，治疗和干预。