Medizinische Klinik, Klinik für Kardiologie und Kreislauferkrankungen, Eberhard Karls-Universität Tübingen, Germany.
Clin Chem. 2011 Jun;57(6):898-904. doi: 10.1373/clinchem.2010.158527. Epub 2011 Apr 7.
Platelet glycoprotein VI (pGPVI) expression is increased in acute coronary syndrome (ACS), reflecting platelet activation. There is no reliable method available to measure pGPVI. Our aim was to develop a bead-based sandwich immunoassay to measure soluble GPVI (sGPVI).
Based on antibodies for sGPVI developed earlier, we established and validated a bead-based sandwich immunoassay in 2438 consecutive patients with stable angina pectoris (SAP; n = 1371), non-ST-elevation myocardial infarction (NSTEMI; n = 724), and ST-elevation MI (STEMI; n = 343). In a subgroup (n = 1011), we measured surface expression of pGPVI using flow cytometry.
The assay revealed a working range of 8-500 ng/L. Intra- and interassay imprecision was <7% and <14%, respectively. Patients with NSTEMI and STEMI showed significantly lower mean sGPVI concentrations than patients with SAP [mean (SD), 8.4 (3.6) μg/L and 8.6 (4.1) μg/L vs 9.8 (4.8) μg/L; P = 0.002], whereas subgroup analysis revealed significantly enhanced pGPVI in NSTEMI (n = 276) and STEMI (n = 80) patients compared with SAP (n = 655) [mean fluorescence intensity (SD), 21.2 (8.1) and 19.8 (6.8) vs 18.5 (7.7); P = 0.002 and P = 0.018]. pGPVI and sGPVI were inversely correlated (r = -0.076; P = 0.023). Area under the ROC curve was 0.716, 95% CI 0.681-0.751, for sGPVI, distinguishing patients with SAP from those with ACS, and was superior (P = 0.044) to the curve of subgroup analysis for pGPVI (0.624, 95% CI 0.586-0.662). sGPVI (P = 0.023) and pGPVI (P = 0.028) had better association with the development of ACS than troponin I (P = 0.055) in the very early stage of disease, based on logistic regression analysis.
This sandwich immunoassay reliably measures sGPVI and may help to identify patients with ACS earlier than other laboratory markers.
血小板糖蛋白 VI（pGPVI）在急性冠状动脉综合征（ACS）中表达增加，反映了血小板的激活。目前尚无可靠的方法来测量 pGPVI。我们的目的是开发一种基于珠子的夹心免疫测定法来测量可溶性 GPVI（sGPVI）。
基于之前开发的用于 sGPVI 的抗体，我们在 2438 例稳定型心绞痛（SAP；n=1371）、非 ST 段抬高型心肌梗死（NSTEMI；n=724）和 ST 段抬高型心肌梗死（STEMI；n=343）患者中建立并验证了基于珠子的夹心免疫测定法。在一个亚组（n=1011）中，我们使用流式细胞术测量了 pGPVI 的表面表达。
该测定法显示出 8-500ng/L 的工作范围。批内和批间精密度分别<7%和<14%。与 SAP 患者相比，NSTEMI 和 STEMI 患者的 sGPVI 浓度明显较低[平均值（标准差），8.4（3.6）μg/L 和 8.6（4.1）μg/L 与 9.8（4.8）μg/L；P=0.002]，而亚组分析显示 NSTEMI（n=276）和 STEMI（n=80）患者的 pGPVI 明显增强与 SAP（n=655）相比[平均荧光强度（标准差），21.2（8.1）和 19.8（6.8）与 18.5（7.7）；P=0.002 和 P=0.018]。pGPVI 和 sGPVI 呈负相关（r=-0.076；P=0.023）。sGPVI 的 ROC 曲线下面积为 0.716（95%CI 0.681-0.751），可区分 SAP 患者和 ACS 患者，优于 pGPVI 亚组分析的曲线（0.624，95%CI 0.586-0.662）（P=0.044）。基于逻辑回归分析，sGPVI（P=0.023）和 pGPVI（P=0.028）与疾病早期 ACS 的发展相关性优于肌钙蛋白 I（P=0.055）。
这种夹心免疫测定法可靠地测量 sGPVI，并可能有助于比其他实验室标志物更早地识别 ACS 患者。
