Clinical Neuroimmunology, Neurology and Department of Biomedicine, University Hospital Basel, Switzerland.
J Neuroimmunol. 2010 Mar 30;220(1-2):114-9. doi: 10.1016/j.jneuroim.2010.01.004. Epub 2010 Feb 1.
The loss of neurological function is closely related to axonal damage. Neurofilament subunits are concentrated in neurons and axons and have emerged as promising biomarkers for neurodegeneration. Electrochemiluminescence (ECL) based assays are known to be of superior sensitivity and require less sample volume than conventional ELISAs.
We developed an ECL based solid-phase sandwich immunoassay to measure the neurofilament heavy chain protein (NfH(SMI35)) in CSF. We employed commercially available antibodies as previously used in a conventional ELISA (Petzold et al., 2003; Petzold and Shaw, 2007). The optimised and validated assay was applied in a reference cohort and defined patient groups.
Analytical sensitivity (background plus three SD) of our assay was 2.4 pg/ml. The mean intra-assay coefficient of variation (CV) was 4.8% and the inter-assay CV 8.4%. All measured control and patient samples produced signals well above background. Patients with multiple sclerosis (MS) (median 46.2 pg/ml, n=95), amyotrophic lateral sclerosis (ALS) (160.1 pg/ml, n=50), mild cognitive impairment/Alzheimer's disease (MCI/AD) (65.6 pg/ml, n=20), Guillain-Barre syndrome (GBS) (91.0 pg/ml, n=20) or subarachnoid hemorrhage (SAH) (345.0 pg/ml, n=20) had higher CSF NfH(SMI35) values than the reference cohort (27.1 pg/ml, n=73, p<0.0001 for each comparison).
The new ECL based assay for NfH(SMI35) in CSF is superior in terms of sensitivity, precision and accuracy to previously published methods (Petzold et al., 2003; Shaw et al., 2005; Teunissen et al., 2009). The improved performance and small sample volume requirement qualify this method in experimental settings and clinical trials designed to perform a number of tests on limited amounts of material.
神经功能的丧失与轴突损伤密切相关。神经丝亚单位集中在神经元和轴突中，已成为神经退行性变有希望的生物标志物。电化学发光（ECL）测定法已知具有较高的灵敏度，并且比传统的 ELISA 需要更少的样品量。
我们开发了一种基于 ECL 的固相夹心免疫测定法来测量 CSF 中的神经丝重链蛋白（NfH（SMI35））。我们使用了商业上可获得的抗体，如先前在传统 ELISA 中使用的抗体（Petzold 等人，2003 年；Petzold 和 Shaw，2007 年）。对优化和验证的测定法进行了参考队列和定义的患者组的应用。
我们的测定法的分析灵敏度（背景加三个 SD）为 2.4 pg/ml。平均批内变异系数（CV）为 4.8%，批间 CV 为 8.4%。所有测量的对照和患者样本均产生远高于背景的信号。多发性硬化症（MS）患者（中位数 46.2 pg/ml，n=95）、肌萎缩侧索硬化症（ALS）患者（160.1 pg/ml，n=50）、轻度认知障碍/阿尔茨海默病（MCI/AD）患者（65.6 pg/ml，n=20）、吉兰-巴雷综合征（GBS）患者（91.0 pg/ml，n=20）或蛛网膜下腔出血（SAH）患者（345.0 pg/ml，n=20）的 CSF NfH（SMI35）值高于参考队列（27.1 pg/ml，n=73，与每项比较相比均 p<0.0001）。
与先前发表的方法（Petzold 等人，2003 年；Shaw 等人，2005 年；Teunissen 等人，2009 年）相比，新的基于 ECL 的 CSF NfH（SMI35）测定法在灵敏度、精密度和准确性方面均具有优势。改进的性能和小的样品量要求使该方法在实验环境和临床试验中具有资格，这些实验和临床试验旨在对有限数量的材料进行多项测试。
