Biosynthetic and Functional Consequences of von Willebrand Disease Mutations

冯维勒布兰德病突变的生物合成和功能后果

• 批准号: 8461835
• 负责人: Jose Aron Lopez
• 金额: $ 61.94万
• 依托单位: BLOODWORKS
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-02-01 至 2018-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8461835
• 关键词: Accounting; Address; Affect; Amino Acids; Binding Sites; Blood Platelets; Categories; Charge; Clinical; Complement; Complex; Cysteine; Disease; Disulfides; Equilibrium; Functional disorder; Hemorrhage; Human; Individual; Induced Mutation; Inherited; Light; Longitudinal Studies; Mass Spectrum Analysis; Metalloproteases; Molecular Conformation; Mutation; Nature; Patients; Phenotype; Plasma; Population; Predisposition; Proteolysis; Questionnaires; Recombinants; Relative (related person); Research; Risk; Structure; Sulfhydryl Compounds; Symptoms; Testing; Time; Variant; Work; base; cohort; disease-causing mutation; disulfide bond; gain of function; gain of function mutation; indexing; kindred; member; monomer; mutant; public health relevance; tool; von Willebrand Disease; von Willebrand Factor

DESCRIPTION (provided by applicant): Von Willebrand disease (VWD) is the most prevalent bleeding disorder in the world, affecting approximately 1% of the human population. It is divided into three general categories, types 1, 2 and 3. In type 2 VWD, most mutations result in replacement of a single amino acid in VWF. The functional consequences of these mutations are difficult to predict because of the complex nature of VWF synthesis and structure. The problem of type 2 VWD will be approached in this application with two specific aims. In Specific Aim 1, a variety of approaches are proposed to examine the effects of type 2B gain-of-function mutations on the disulfide bond structure of the VWF A1-A2-A3 region. These studies address the hypothesis that mutations that change the number of Cys residues or increase the negative charge in the region of the Cys1272-Cys1458 disulfide bond alter the disulfide-bond structure of the region. The disulfide-bond structure of 2B VWF mutants will be examined by mass spectrometry (MS) and correlated with functional alterations. In Specific Aim 2, plasma from a large number of well-characterized patients from a type 2 VWD kindred will be evaluated with a mathematical index of VWF quality and quantity that takes into account the percentage of mutant monomers incorporated into multimers, the relative content of multimers of different sizes, and the VWF quantity. This index will be correlated with VWF functional parameters and with the bleeding phenotype as quantified with a validated bleeding score questionnaire. These studies will be complemented with a longitudinal study of six patients with type 2B VWD (mutation R1308C) to compare the index with contemporaneously determined parameters of VWF function. It is expected that these studies will delineate both intra- and inter-individual variation in the VWF quality index. In aggregate, the proposed studies will shed light on the complex pathophysiology of type 2 VWD and have the potential to provide an accurate and quantitative assessment of bleeding risk in VWD patients.

描述（由申请人提供）：冯·威尔布兰氏病（VWD）是世界上最普遍的出血疾病，影响了大约1％的人口。它分为三种类别，类型1、2和3。在2型VWD中，大多数突变导致在VWF中替换单个氨基酸。由于VWF合成和结构的复杂性质，这些突变的功能后果很难预测。在本应用程序中将解决2型VWD的问题，并具有两个具体的目标。在特定的目标1中，提出了多种方法来检查2B型功能获得突变对VWF A1-A2-A3区域二硫键结构的影响。这些研究解决了以下假设：改变CYS残基数量或增加CYS1272-CYS1458二硫键键的突变会改变该区域的二硫键结构。 2B VWF突变体的二硫键结构将通过质谱（MS）检查，并与功能改变相关。在特定的目标2中，将通过VWF质量和数量的数学指数评估来自大量2型VWD Kindred的大量特征良好的患者的等离子体，这些数学指数考虑到掺入多聚体的突变单体的百分比，不同尺寸的多模的相对含量，以及不同尺寸的多模含量，以及VWF数量。该指数将与VWF功能参数以及通过经过验证的出血评分问卷量化的出血表型相关。这些研究将与六名2B型VWD（突变R1308C）患者进行纵向研究，以将指数与同时确定的VWF功能参数进行比较。可以预期，这些研究将描述VWF质量指数的内部和个体间变化。总体而言，拟议的研究将阐明2型VWD的复杂病理生理学，并有可能对VWD患者的出血风险进行准确和定量的评估。