Shaw Gerry, Yang Cui, Ellis Rebecca, Anderson Kevin, Parker Mickle J, Scheff Stephen, Pike Brian, Anderson Douglas K, Howland Dena R
Department of Neuroscience, University of Florida College of Medicine, Gainesville, USA.
Biochem Biophys Res Commun. 2005 Nov 4;336(4):1268-77. doi: 10.1016/j.bbrc.2005.08.252.
Several lines of reasoning suggest that the phosphorylated axonal form of the neurofilament subunit NF-H is likely to be released from damaged and diseased neurons in significant amounts. Detection of this protein in serum or CSF might therefore provide information about the presence and degree of neuronal loss. We therefore developed a sensitive NF-H ELISA capable of detecting picogram quantities of phosphorylated NF-H (pNF-H). This assay showed that soluble pNF-H immunoreactivity is readily detectable in the sera of adult rats following various types of experimental spinal cord injury (SCI) and traumatic brain injury (TBI), but is undetectable in the sera of normal animals. Here we describe details of the time course and extent of serum pNF-H expression following experimental SCI and TBI. Following SCI, serum pNF-H showed an initial peak of expression at 16h and a second, usually larger, peak at 3 days. Following TBI, lower levels of serum pNF-H were detected with a peak at 2 days post-injury. We also show that the higher levels of pNF-H released from injured spinal cord as compared to brain are in line with the approximately 20-fold higher levels of pNF-H present in spinal cord. These findings suggest that serum levels of pNF-H immunoreactivity may be used to conveniently monitor neuronal damage and degeneration in experimental and presumably clinical situations.
几条推理线索表明，神经丝亚基NF-H的磷酸化轴突形式很可能会从受损和患病的神经元中大量释放出来。因此，在血清或脑脊液中检测这种蛋白质可能会提供有关神经元丢失的存在和程度的信息。我们因此开发了一种灵敏的NF-H酶联免疫吸附测定法（ELISA），能够检测皮克量的磷酸化NF-H（pNF-H）。该测定法表明，在成年大鼠遭受各种类型的实验性脊髓损伤（SCI）和创伤性脑损伤（TBI）后，其血清中可溶性pNF-H免疫反应性很容易检测到，但在正常动物的血清中则检测不到。在此，我们描述了实验性SCI和TBI后血清pNF-H表达的时间进程和程度的详细情况。SCI后，血清pNF-H在16小时出现首个表达峰值，在3天时出现第二个通常更大的峰值。TBI后，检测到的血清pNF-H水平较低，在受伤后2天出现峰值。我们还表明，与脑相比，从受损脊髓释放的pNF-H水平更高，这与脊髓中pNF-H水平高出约20倍相符。这些发现表明，血清中pNF-H免疫反应性水平可用于方便地监测实验性以及可能的临床情况下的神经元损伤和变性。
