STUDIES ON THE PATHOPHYSIOLOGY OF THROMBOEMBOLIC DISEASES WITH SPECIAL REFERENCE TO THE UNDERLYING IMPAIRED BLOOD COAGULATION AND ITS REGULATION

血栓性疾病的病理生理学研究，特别是潜在的凝血受损及其调节

基本信息

批准号：
11470250
负责人：
MATSUDA Michio
金额：
$ 7.81万
依托单位：
Jichi Medical School
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B).
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2000
项目状态：
已结题

项目摘要

1. Studies on the hereditary dysfibrinogens associated with thrombosis and/or bleeding In fibrinogen (Fbg) Osaka VI, a hereditary dysfibrinogen derived from a 36-year-old woman with a history of severe bleeding on two childbirths, we have identified an exchange of T to A in the stop codon (TAG) of the fibrinogen Bβ-chain gene leading to formation of a codon for Lys (AAG). Thus, 12 amino acid residues are translated to elongate the aberrant Bβ-chain and indeed, this extension has been confirmed by sequence analysis. There is a Cys residue next to the new carboxyl-terminus, which forms a disulfide bridge with its counterpart in another dysfibrinogen molecule. Thus, two types of end-linked Fbg-dimers exist in the patient's Fbg, i.e., a bilayer dimer end-linked at both ends and a longitudinally aligned dimer end-linked at either one of the two carboxyl-terminal ends. These dimers had been predicted by SDS-PAGE run under non-reducing conditions, where two molecular species, i.e., a normal s … More ized and a double-sized Fbg species had been visualized.By transmission electron microscopy, the fibrin fibers appear extremely thin but the fibrin networks are highly branched and compact as compared with those of normal fibrin clots. We thus hypothesized that the abnormal branching may occur at the points in the double-stranded fibrin proitofibrils, where the abnormal dimeric molecules are incorporated. Furthermore, the Osaka VI fibrin clots are mechanically readily compressible leading to form very fragile fibrin clots. These fibrin clots may fail to exert their hemostatic function and thereby lead to easy bleeding (Blood 96(12) : 3779-3785, 2000). These findings seem to be comparable to those of Fbg Marburg associated with thrombosis besides bleeding after surgery. Namely, this dysfibringen also forms fine fibrin fibers and compact fibrin networks, but the fibrin fibers are highly resistant against plasmin, accounting for thromboembolic complications (Blood 91(9) : 3282-3288, 1999).We have also studied the role of oligosacharides linked to Asn residue due to formation of a new glycosylation sequence of Asn-X-Thr/Ser in Fbgs Asahi and Lima (Ann NY Acad Sci, in press). Matsuda, the chief researcher, had chances to review these data at several international congresses and symposia (see the attached publication list).2. Other studies1) We have produced a monoclonal antibody, IF-123, that specifically recognizes elastase-digests of human fibrinogen/fibrin, and its epitope determination and clinical application have been successfully attempted (Blood 96(5) : 1721-1728, 2000).2) A novel strategy for the tumor angiogenesis-targeted gene therapy has been established by generation of angiostatin from endogenous plasminogen by protease gene transsfer in mice (Cancer Gene Therapy 7(5) : 589-596, 2000). Less

1. Studies on the hereditary dysfibrinogens associated with thrombosis and/or bleeding In fibrinogen (Fbg) Osaka VI, a hereditary dysfibrinogen derived from a 36-year-old woman with a history of severe bleeding on two childrenbirths, we have identified an exchange of T to A in the stop codon (TAG) of the fibrinogen Bβ-chain gene leading to formation of a codon for Lys（AAG）。这是12种氨基酸的翻译成异常的Bβ链，实际上，通过序列分析证实了这一扩展。新的羧基末端旁边有一个CYS居住，该羧基末端在另一个动物纤维蛋白原分子中形成了二硫键。这是患者的FBG中存在两种类型的终端FBG二聚体，即两端的双层二聚体端连接，并且在两个羧基末端的任何一个末端都链接了末端的二聚体。这些二聚体是通过在非还原条件下运行的SDS-PAGE进行预测的，其中两个分子物种，即正常的S…更多的IZ型和双尺寸的FBG物种被可视化。通过透射电子显微镜，纤维蛋白纤维看起来非常薄，但纤维蛋白网络非常稀薄，但与正常的纤维纤维纤维纤维蛋白相比，纤维蛋白是高度分支的。因此，我们假设异常分支可能发生在双链纤维蛋白原纤维中的点，其中掺入异常的二聚体分子。此外，大阪VI纤维蛋白凝块在机械上易于压缩，从而形成非常脆弱的纤维蛋白血块。这些纤维蛋白血块可能无法发挥其止血功能，从而导致容易出血（血液96（12）：3779-3785，2000）。除了手术后出血外，这些发现似乎与与血栓形成相关的FBG Marburg的发现相媲美。也就是说，这种不纤维纤维还形成细纤维蛋白纤维和紧凑的纤维蛋白网络，但是纤维蛋白纤维对纤溶酶具有很高的抗性，这是对血小板并发症的解释（血液91（9）：3282-3288，1999）。 FBGS Asahi和Lima中的ASN-X-THR/SER（Ann Ny Acad Sci，印刷中）。首席研究员Matsuda有机会在几个国际大会和专题讨论会上审查这些数据（请参阅所附的出版物列表）。2。其他研究1）我们已经产生了一种单克隆抗体IF-123，该抗体特别识别人类纤维蛋白原/纤维蛋白的弹性酶消化，其表位确定和临床应用已成功尝试（Blood 96（5）：1721-1728，2000）。小鼠蛋白酶基因转移的内源性纤溶酶原（癌基因治疗7（5）：589-596，2000）。较少的