ANALYSIS OF IGA FROM IGA-FIBRONECTIN COMPLEX IN THE PATIENT WITH IGA NEPHROPATHY AND ITS EFFECT ON THE FUNCTION OF RENAL CELIS IN CULTURE.

IGA 肾病患者 IGA-纤连蛋白复合物的 IGA 分析及其对培养中肾细胞功能的影响。

• 批准号: 02670422
• 负责人: WAGA Shinobu
• 金额: $ 1.34万
• 依托单位: HIROSAKI UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1990
• 资助国家: 日本
• 起止时间: 1990 至 1992
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-02670422/
• 关键词: IgA nephropathy; IgA-fibronectin complex; Serum fibronectin; Fraqmented fibronectin; IgA; IgAーフィブロネクチン複合体

IgA-fibronectin complex(IgA-F・C) have been in the serum of patients with IgA nephropathy(IgAN) with higher incidence than other serological markers for IgAN.The purpose of this study is ; 1. to determine the incidence of IgA-F・C in pediatric patiens with IgAN in addition to looking at the basis of this assay system using collagen type I -coated microtiter plate, and 2. to analyze the formation of this complex in patients, with Western blot utilizing a set of monoclonal anti-human fibronectin antibodies for materials from heparin-affinity column treated by patient's serum.Result : 1. Significant detection of IgA-F・C in IgAN patients was observed in 52%, which did not correlate with severity of disease or an attack of gross hematuria. Elevated IgA-F・C was also detected in some of patients with Henoch-Schonlein purpura nephritis and active stage of juvenile rheumatoid arthritis. A few of definite IgAN patient with low activity of IgA-F・C turned out to be significant by treatment with gelatin-column.2. Silver-staining of SDS-PAGE for eluate of gelatin-, or heparin-column showed that binding proteins of serum to each column contained proteins of wide-ranged molecular weight, and some of them demonstrated only in patients but not controls. The extra-proteins was shown especially in the material from heparin-affinity column. These findings were confirmed by Western blot procedure, suggesting that serum fibronectin was degraded, which must be neglected in a established protocol for isolation of fibronectin. Reactivity of some monoclonal antibodies to degraded fibronectins was specific to patient.3. Application of purified IgA onto immobilized fibronectin fragments from patient and cathepsin D-digested fibronectin demonstrated that 42 kilodalton fragment, produced both by patient and cathepsin D proteolyis, was bound to IgA.These findings may have ramifications in the origin and possible pathogenetic importance for the etiology of IgAN.

IgA-纤维连接蛋白复合物（IgA-F·C）在伊加肾病（IgAN）患者血清中的发生率高于其他血清学指标。确定IgA-F·C在儿童IgAN患者中的发生率，以及使用I型胶原包被的微量滴定板观察该测定系统的基础;和2.用一组抗人纤连蛋白单克隆抗体对经患者血清处理的肝素亲和柱材料进行Western blot分析，以分析患者体内纤连蛋白复合物的形成。IgAN患者IgA-F·C阳性率为52%，与疾病严重程度及肉眼血尿发作无关。部分紫癜性肾炎和幼年型类风湿关节炎活动期患者血清IgA-F·C水平升高。结论：1.少数IgAN患者IgA-F·C活性降低，明胶柱治疗后有明显意义。SDS-PAGE银染显示，血清中与明胶或肝素柱结合的蛋白质分子量范围较宽，其中有些蛋白质仅在患者血清中出现，而在对照血清中未出现。肝素亲和层析柱分离的样品中含有大量的外源蛋白。这些发现通过Western印迹程序证实，表明血清纤连蛋白被降解，这在用于分离纤连蛋白的既定方案中必须被忽略。某些单克隆抗体对降解纤维连接蛋白的反应性具有患者特异性.将纯化的伊加固定在患者和组织蛋白酶D消化的纤维连接蛋白片段上，结果表明，患者和组织蛋白酶D蛋白水解产生的42千道尔顿片段与伊加结合。这些发现可能对IgAN的起源和可能的致病重要性产生影响。