Neprilysin and Peripheral Clearance of Amyloid Peptides

脑啡肽酶和淀粉样肽的外周清除

• 批准号: 7858439
• 负责人: Louis B. Hersh
• 金额: $ 18.48万
• 依托单位: UNIVERSITY OF KENTUCKY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-06-15 至 2012-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7858439
• 关键词: Abeta clearance; Alzheimer' s Disease; Amyloid; Amyloid beta-Protein; Amyloid beta-Protein Precursor; Antibodies; Binding; Blood; Blood Cells; Blood Platelets; Bone Marrow Cells; Bone Marrow Stem Cell; Bone Marrow Transplantation; Brain; Cell membrane; Cell surface; Cells; Chimera organism; Chimeric Proteins; Complement; Enzymes; Epitopes; Erythrocytes; Ganglioside GM1; Gelsolin; Hematopoietic; Human; Hydrolysis; Impaired cognition; Injection of therapeutic agent; Leukocytes; Link; Lymphocyte; Measures; Methods; Mus; Neprilysin; Peptide Hydrolases; Peptides; Peripheral; Plasma; Play; Principal Investigator; Proteins; Public Health; Role; Subfamily lentivirinae; Tail; Testing; Therapeutic; Transgenic Mice; Translations; Transplantation; Veins; amyloid peptide; human subject; immunogenicity; morris water maze; mouse model; novel therapeutic intervention; prevent; programs

DESCRIPTION (provided by applicant): It has been shown that peripheral clearance of amyloid beta peptides reduces amyloid beta peptide levels in the brain through what has been termed a "sink effect". We have exploited this "sink effect" by showing that the peptidase neprilysin, when expressed peripherally on leukocytes reduced amyloid beta peptide levels in the brain of a hAPP transgenic mouse model of Alzheimer's disease. To obtain peripheral neprilysin expression we transplanted bone marrow stem cells transduced with lentivirus expressing neprilysin to a recipient hAPP transgenic mouse. We now propose to further develop peripheral expression of neprilysin as a therapeutic treatment for AD. Two specific aims directed at further developing peripheral neprilysin expression, without the need for bone marrow transplantation, are proposed: SPECIFIC AIM 1. To test the use of a single chain antibody-neprilysin (NEP) chimeric protein targeted to red blood cells to lower brain amyloid beta peptide levels. Chimeric proteins composed of a single chain antibody targeted to a mouse erythrocyte epitope fused with neprilysin will be used to produce erythrocyte bound neprilysin which will be tested for the ability to lower brain amyloid beta peptide levels. SPECIFIC AIM 2. To test the use of a myristoylated-neprilysin to attach NEP to hematopoietic cells. We will generate a form of neprilysin in which a myristoyl-peptide is linked to the C-terminus. This myristoyl-NEP will be used to produce peripheral NEP by insertion into the plasma membrane of hematopoietic cells and tested for the ability to lower brain amyloid beta peptide levels. We have as an overall objective the translation of one of these methods to the testing of human subjects. PUBLIC HEALTH RELEVENCE: The focus of this proposal is to develope a new therapeutic approach for treating Alzheimer's disease. We propose to express the enzyme neprilysin on blood cells where it can degrade plasma amyloid beta peptides leading to a lowering of brain amyloid beta peptides which are known to play a major role in causing Alzheimer's disease.

描述（由申请人提供）：研究表明，淀粉样β肽的外周清除通过所谓的“下沉效应”降低了大脑中淀粉样β肽的水平。我们已经利用了这种“水槽效应”，通过显示肽酶脑啡肽酶，当在白细胞外周表达时，降低了阿尔茨海默病的hAPP转基因小鼠模型脑中的淀粉样β肽水平。为了获得外周脑啡肽酶表达，我们将用表达脑啡肽酶的慢病毒转导的骨髓干细胞移植到受体hAPP转基因小鼠中。我们现在建议进一步开发脑啡肽酶的外周表达作为AD的治疗性治疗。两个具体的目标，旨在进一步发展外周脑啡肽酶的表达，而不需要骨髓移植，提出了：特异性目的1。测试靶向红细胞的单链抗体-脑啡肽酶（NEP）嵌合蛋白降低脑淀粉样蛋白β肽水平的用途。由靶向小鼠红细胞表位的单链抗体与脑啡肽酶融合组成的嵌合蛋白将用于产生红细胞结合的脑啡肽酶，将测试其降低脑淀粉样蛋白β肽水平的能力。具体目标2.测试使用肉豆蔻酰化脑啡肽酶将NEP附着于造血细胞。我们将产生一种形式的脑啡肽酶，其中肉豆蔻酰肽连接到C-末端。该肉豆蔻酰-NEP将用于通过插入造血细胞的质膜来产生外周NEP，并测试降低脑淀粉样蛋白β肽水平的能力。我们的总体目标是将这些方法之一转化为人类受试者的测试。公共卫生解放：该提案的重点是开发一种治疗阿尔茨海默病的新方法。我们建议在血细胞上表达脑啡肽酶，在那里它可以降解血浆淀粉样β肽，导致脑淀粉样β肽的降低，已知脑淀粉样β肽在引起阿尔茨海默病中起主要作用。