Pathobiological Study on Congenital Deficiency of Vitamin K-dependent Protein S.

先天性维生素K依赖性蛋白S缺乏症的病理生物学研究。

• 批准号: 62480433
• 负责人: SUZUKI Koji
• 金额: $ 4.03万
• 依托单位: The University of Tokushima (1989)Mie University (1987-1988)
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1987
• 资助国家: 日本
• 起止时间: 1987 至 1989
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-62480433/
• 关键词: Protein S; Protein C; C4b-binding protein; Congenital protein S deficiency; Congenital thrombophilia; Protein C anticoagulant pathway; Vitamin K-dependent proteins; Monoclonal antibody; C_4b結合蛋白質(C_4bp); PS・C_4bp複合体; 遊離型プロテインS; 先天性プロテインS欠損症; C

[Aim] Protein S is a vitamin K-dependent plasma protein that plays a role as a cofactor for activated protein C (APC). APC is another vitamin K-dependent serine protease which inactivates blood coagulation cofactors, Factor Va and Factor VIIIa. Recently, patients with congenital deficiency of protein S or protein C have frequently been found as patients having severe thromboembolic diseases. Thus, protein S is involved in concert with APC in regulation of blood coagulation in vivo as well as in vitro. Recently, protein S in plasma was found to exist in two forms, one is a functionally active free form and the other is a functionally inactive complex form with a complement.component C4b-binding protein (C4bp) . The present study was performed to elucidate the pathobiology of protein S in patients with congenital deficiency of protein S.[Results and Discussion] (1) Thirty seven patients in two families with congenital protein S deficiency were analyzed, then it was found that plasma protein S activity in these patients appeared to correlate with the amount of-free form protein S, but not with that of total protein S nor C4bp. (2) Seventeen monoclonal antibodies for C4bp were prepared and their epitopes on C4bp molecule were determined. Also a binding site for protein S on C4bp was determined. (3) Fifteen monoclonal antibodies for protein S were prepared and epitopes for the respective antibodies were determined. Enzyme immunoassay methods to determine free form protein S, total protein S and protein S-C4bp complex were established. (4) Function of protein S-C4bp complex was investigated and it was found that the complex inhibits competitively the interaction between free form protein S and APC which results in the decrease of cofactor activity of free form protein S. These results indicate that in plasma of patients with congenital deficiency of protein S, the cofactor activity of protein S depends on the amounts of both free form and complex form of protein S.

【目的】蛋白S是一种维生素k依赖性血浆蛋白，作为活化蛋白C （APC）的辅助因子。APC是另一种依赖维生素k的丝氨酸蛋白酶，它能使凝血辅助因子Va和viia失活。近年来，先天性蛋白S或蛋白C缺乏的患者经常被发现患有严重的血栓栓塞性疾病。因此，蛋白S与APC共同参与体内和体外的凝血调节。近年来，在血浆中发现蛋白S以两种形式存在，一种是功能活跃的游离形式，另一种是功能无活性的复合物形式，具有互补组分c4b结合蛋白（C4bp）。【结果与讨论】(1)对2个先天性蛋白S缺乏家族的37例患者进行分析，发现这些患者血浆蛋白S活性似乎与游离态蛋白S的数量相关，但与总蛋白S和C4bp无关。(2)制备了17种C4bp单克隆抗体，并确定了它们在C4bp分子上的表位。同时还确定了C4bp上S蛋白的一个结合位点。(3)制备了15种针对蛋白S的单克隆抗体，并确定了各自抗体的表位。建立酶免疫分析法测定游离蛋白S、总蛋白S和蛋白S- c4bp复合物。(4)对S- c4bp蛋白复合物的功能进行了研究，发现该复合物竞争性地抑制自由形式蛋白S与APC的相互作用，导致自由形式蛋白S的辅因子活性降低。结果表明，先天性蛋白质S缺乏患者血浆中，蛋白质S的辅因子活性取决于蛋白质S的自由形式和复合形式的量。

项目成果

Suzuki, K. & Kamiya, T.: "Congenital deficiency of protein S." Acta Haematol. Jpn. 51: 1298-1301, 1988.

铃木，K.

Nishioka, J. & Suzuki, K.: "Inhibition of cofactor activity of protein S by a complex of protein S and C4b-binding protein: Evidence for an inactive ternary complex formation between protein S, C4b-binding protein and activated protein C." J. Biol. Chem.

西冈，J.

鈴木宏治: 日本臨床・特集分子血液学. 45. 2971-2982 (1987)

铃木浩二：日本临床专题分子血液学。 45. 2971-2982 (1987)

鈴木宏治: 日本血液学会雑誌. 51. 1298-1301 (1988)

铃木浩二：日本血液学会杂志 51. 1298-1301 (1988)。

Suzuki,K.;Deyashiki,Y.;Nishioka,J.;Akira,M.;Kurachi,K.;Hashimoto,S.: J.Biol.Chem.262. 611-616 (1987)

铃木，K.；出屋敷，Y.；西冈，J.；阿基拉，M.；库拉奇，K.；桥本，S.：J.Biol.Chem.262。