Autoantibodies against human prothrombin ; epitope and thrornbogeneicity

抗人凝血酶原的自身抗体；

• 批准号: 15591041
• 负责人: ATSUMI Tatsuya
• 金额: $ 2.3万
• 依托单位: Hokkaido University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2003
• 资助国家: 日本
• 起止时间: 2003 至 2004
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-15591041/
• 关键词: prothrombin; lupus anticoagulant; antiphospholipid syndrome; thrombosis; monoclonal antibody; thrombin; phosphatidylserine

Phosphatidylserine dependent antiprothrombin antibodies (aPS/PT) are closely associated with the clinical manifestations of antiphospholipid syndrome (APS) and LA, whilst neither in vitro nor in vivo properties of aPS/PT in thrombin generation have been clarified. The purpose of this study is to investigate the in vitro roles of aPS/PT in thrombin generation. The reactivity of monoclonal antiprothrombin antibodies against phosphatidylserine, phosphatldylserine bound prothrombin, and prothrombin on irradiated/non-irradiated plates were examined by enzyme-linked immunosorbent assay (ELISA). To investigate the epitopes for aPS/PT, an inhibition ELISA using monoclonal antiprothrombin antibodies and purified IgG from APS patients was performed. The effects of mouse monoclonal phosphatidyserine dependent anti-human prothrombin antibody (MoaPS/PT) on thrombin generation were evaluated by a chromogenic assay, using the prothombinase complex [phospholipid, CaCl_2, human purified factor Va (FVa) … More , human factor Xa (FXa), and human purified prothrombin]. Thrombin generation was measured by a quantitative analysis using a specific substrate for thrombin (S2238). We established mouse monoclonal antibodies, 231D and 51A6. 231D only bound to phosphatidylserine bound prothrombin, and was considered as aPSIPT. 51A6 bound to both phosphatidylserine bound prothrombin and prothrombin alone on irradiated and non-irradiated plates, but not to phosphatidylserine alone. The binding of IgG from APS patients to phosphaydilserin/prothrombin complex was inhibited by 231D between 35-70%, but not by 51A6. In the presence of low concentration of FVa (0.1ng/ml), 231D increased thrombin generation up to 87% in a dose-dependent manner. In contrast, when high concentration of FVa (1.0 ng/ml) were added, 231D decreased thrombin generation up to 35%. Under a constant concentration of FVa, high concentration of FXa enhanced the effect of 231D. 51A6 showed minor inhibition of thrombin generation in any conditions. 231D had similar characteristic to autoimmune aPS/PT that react only with phosphatidylserine bound prothrombin. 231D and APS patients' IgG may share the epitope on phosphaydilserin/prothrombin complex, suggesting that 231D represents the properties of autoimmune aPS/PT. The in vitro effects of 231D on thrombin generation are dual-factorial according to the FVa and FXa balance, therefore serving as a clue fort the LA paradox. Less

磷脂酰丝氨酸依赖的抗凝血酶原抗体(APS/PT)与抗磷脂综合征(APS)和LA的临床表现密切相关，但APS/PT在体内和体外对凝血酶生成的影响尚不清楚。本研究的目的是探讨APS/PT在体外凝血酶生成中的作用。用酶联免疫吸附试验(EL ISA)检测抗磷脂酰丝氨酸、磷脂酰丝氨酸结合的凝血酶原和抗凝血酶原的单抗在照射和未照射平板上的反应性。为了研究APS/PT的抗原表位，用抗凝血酶原的单抗和纯化的APS患者的免疫球蛋白进行了抑制性酶联免疫吸附试验。以原酶复合体[磷脂，CaCl2，人纯化因子Va(FVA)…]为模板，用发色法研究了小鼠依赖磷脂酰丝氨酸的抗人凝血酶原抗体对凝血酶生成的影响更多，人凝血因子Xa(FXA)和人纯化的凝血酶原]。凝血酶生成通过使用凝血酶的特定底物的定量分析来测量(S2238)。我们建立了小鼠单抗231D和51A6。231D只与磷脂酰丝氨酸结合的凝血酶原结合，被认为是aPSIPT。51A6在照射和非照射平板上均可与磷脂酰丝氨酸结合的凝血酶原和凝血酶原单独结合，但不能单独与磷脂酰丝氨酸结合。~(231)D可抑制APS患者的免疫球蛋白与磷脂酰二丝氨酸/凝血酶原复合体的结合，而~(51)A_6对其抑制作用在35~70%之间。在低浓度FVA(0.1 ng/ml)存在下，231D可使凝血酶生成增加87%，并呈剂量依赖关系。相反，当加入高浓度的FVA(1.0 ng/ml)时，231D使凝血酶的生成减少了35%。在FVA浓度不变的情况下，高浓度的FXA增强了231D的作用。51A6在任何条件下对凝血酶生成均有轻微抑制作用。231D与自身免疫性APS/PT相似，只与磷脂酰丝氨酸结合的凝血酶原反应。231D和APS患者的免疫球蛋白可能具有相同的磷脂酰二丝氨酸/凝血酶原复合体表位，提示231D代表自身免疫性APS/PT的特性。根据FVA和FXA的平衡，231D在体外对凝血酶生成的影响是双因素的，因此可以作为LA悖论的线索。较少

项目成果

Phosphatidylserine-dependent antiprothrombin antibodies are not useful markers for high-risk women with recurrent miscarriages.

磷脂酰丝氨酸依赖性抗凝血酶原抗体对于反复流产的高危女性来说并不是有用的标记。

• 发表时间: 2004
• 期刊: Fertil Steril 82
• 作者: Sugiura-Ogasawara M;Atsumi et al.
• 通讯作者: Atsumi et al.

Yasuda S, Atsumi t, Ieko M et al.: "Nicked beta2-glycoprotein I : A marker of cerebral infarct and a novel role in the negative feedback pathway of extrinsic fibrinolysis."Blood. (in press).

Yasuda S、Atsumi t、Ieko M 等人：“切口 β2-糖蛋白 I：脑梗塞的标志物以及外源性纤溶负反馈途径中的新作用。”血液。

Antiprothrombin antibodies-are they worth assaying?

• DOI: 10.1016/j.thromres.2004.08.024
• 发表时间: 2004-01-01
• 期刊: THROMBOSIS RESEARCH
• 影响因子: 7.5
• 作者: Atsumi, T;Amengual, O;Koike, T
• 通讯作者: Koike, T

Nicked beta2-glycoprotein I: a marker of cerebral infarct and a novel role in the negative feedback pathway of extrinsic fibrinolysis.

带缺口的β2-糖蛋白I：脑梗塞的标志物和外源性纤溶负反馈途径中的新作用。

• 发表时间: 2004
• 期刊: Blood
• 影响因子: 20.3
• 作者: S. Yasuda;T. Atsumi;M. Ieko;E. Matsuura;Kazuko Kobayashi;J. Inagaki;H. Kato;Hideyuki Tanaka;M. Yamakado;M. Akino;Hisatoshi Saitou;Y. Amasaki;S. Jodo;O. Amengual;T. Koike
• 通讯作者: T. Koike

Nicked beta2-glycoprotein 1 : A marker of cerebral infarct and a novel role in the negative feedback pathway of extrinsic fibrinolysis.

带缺口的β2-糖蛋白1：脑梗塞的标志物和外源性纤溶负反馈途径中的新作用。

• 发表时间: 2004
• 期刊: Blood 103
• 作者: Yasuda S;Atsumi T et al.
• 通讯作者: Atsumi T et al.