Protein C activation in endothelial cells is inhibited under the presence of anticardiolipin antibody in ischemic stroke patients

缺血性中风患者抗心磷脂抗体存在下，内皮细胞中的蛋白 C 活化受到抑制

• 批准号: 07670731
• 负责人: KITAGAWA Yasuhisa
• 金额: $ 0.45万
• 依托单位: Tokai University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07670731/
• 关键词: anticardiolipin antibody; cerebral infaretion; protein C; endothelial cell; antiphospholipid antibody; thrombosis; プロテインC

INTRODUCTION : Anticardiolipin antibody (aCL) is considered to be one of the contributory factors in the development of cerebral infarction. A number of sites exist in the coagulation system where interaction with aCL may lead to thrombosis. However, the precise mechanism of action of aCL remains unknown. Human activated protein C functions as a potent anticoagulant in human plasma by inhibiting the activity of coagulation cofactors Va and VIIIa. The purpose of the present study was to investigate the effect of serum IgG fraction obtained from ischemic stroke patients on the rate of protein C activation in cultured human endothelial cells from the umbilical cord veins.SUBJECTS AND METHODS : The rate of protein C activation was examined in the following groups. We had 10 ischemic stroke patients with positive IgG aCL.These comprised 7 patients with cerebral infarction related SLE (Group 1) and 3 patients without an immunological background including SLE (Group 2). We also examined in 6 … More non-SLE related ischemic stroke patients without aCL (Group 3), 14 SLE patients with aCL who did not develop ischemic stroke (Group 4), 6 SLE patients without stroke and aCL (Group 5) and 6 normal controls (Group 6). Confluent endothelial cells were incubated with buffer or IgG obtained from the patients (7 mg/ml) for 1 hour at 37ﾟC.Purified human protein C (1 nM/well) and thrombin (0.04 nM/well) were added. After 2 hours incubation at 37ﾟC,the rate of protein C activation was determined by amidolytic assay employing P-Glu-Pro-Arg-MNA as a substrate. The degree of activation of protein C was expressed as the percent change in the measured absorbance between the presence and absence of the IgG fraction. A negative percent change indicated inhibition of protein C activation.RESULTS : In SLE related ischemic stroke with positive aCL (Group 1), 5 of the 7 patients revealed a negative percent change which indicated inhibition of the rate of protein C activation by addition of the IgG fraction. The mean percent change of absorbance in these 7 patients was -7.2% (range, from -21.4% to+4.5%). In the 3 non-SLE stroke patients with positive aCL (Group 2), the percent changes in absorbance were -2.0%, -9.8% and -6.6%, respectively. On the other hand, IgG fraction did not appreciably influence the activation of protein C in the patients of Group 3 (the mean parcent change of absorbance, +0.1%), Group 4 (-0.5%) and Group 5 (+0.3%). In the normal controls, the mean percent change in the measured absorbance was +0.6%.CONCLUSION : Our results appear to indicate that aCL in IgG fractions can interfere with interactions among thrombin, protein C and thrombomodulin on the surface of endothelial cells. Impairment of the rate of activation of protein C could play a role in the development of ischemic stroke. Less

简介：抗心磷脂抗体（aCL）被认为是脑梗塞发生的促成因素之一，凝血系统中存在许多与aCL相互作用可能导致血栓形成的部位，但aCL的确切作用机制尚不清楚。人类活化蛋白 C 通过抑制凝血辅助因子 Va 和 VIIIa 的活性，在人血浆中发挥有效的抗凝作用。本研究的目的是研究血清的作用。从缺血性中风患者获得的 IgG 组分对脐带静脉培养的人内皮细胞中蛋白 C 活化率的影响。 对象和方法： 我们检查了 10 名呈阳性的缺血性中风患者的蛋白 C 活化率。 IgG aCL。这些患者包括 7 名患有脑梗塞相关 SLE 的患者（第 1 组）和 3 名没有包括 SLE 在内的免疫学背景的患者（第 2 组）。还对 6 名无 aCL 的非 SLE 相关缺血性中风患者（第 3 组）、14 名患有 aCL 但未发生缺血性中风的 SLE 患者（第 4 组）、6 名无中风和 aCL 的 SLE 患者（第 5 组）和 6 名正常患者进行了检查对照（第6组）与从患者获得的缓冲液或IgG（7mg/ml）在3℃下孵育1小时。 37°C。加入纯化的人蛋白C（1 nM/孔）和凝血酶（0.04 nM/孔），在37°C下孵育2小时后，通过使用P-Glu-的酰胺分解测定法测定蛋白C的活化率。 Pro-Arg-MNA 作为底物，表示为 IgG 组分存在和不存在之间测得的吸光度变化百分比（负百分比）。结果：在具有阳性 aCL 的 SLE 相关缺血性中风（第 1 组）中，7 名患者中有 5 名显示出负百分比变化，这表明通过添加 IgG 部分抑制了蛋白 C 激活速率。在 3 名 aCL 阳性的非 SLE 卒中患者中，这 7 名患者的吸光度平均变化百分比为 -7.2%（范围为 -21.4% 至 +4.5%）。 2) 中，吸光度变化百分比分别为-2.0%、-9.8% 和-6.6%。另一方面，IgG 分数对第 3 组患者中蛋白 C 的激活没有明显影响（平均变化百分比）。在正常对照中，测得的吸光度的平均百分比变化为（+0.1%）、第 4 组（-0.5%）和第 5 组（+0.3%）。 +0.6%。结论：我们的结果似乎表明 IgG 组分中的 aCL 可以干扰内皮细胞表面凝血酶、蛋白 C 和血栓调节蛋白之间的相互作用。蛋白 C 激活速率的损害可能在发育中发挥作用。缺血性中风较少。

项目成果

Kitagawa Y et al: "Protein C activation in endothelial cell is inhibited under the presence of anticadiolipin antibody in ischemic Stroke patients" J Cereral Blood Flow Metabol. 15 (suppl 1). S684- (1995)

Kitakawa Y 等人：“缺血性中风患者中，内皮细胞中的蛋白 C 活化在抗心磷脂抗体的存在下受到抑制”J Cereral Blood Flow Metabol。