Hayashi Takahito, Ago Kazutoshi, Ago Mihoko, Ogata Mamoru
Department of Legal Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima 890-8544, Japan.
Leg Med (Tokyo). 2009 Apr;11 Suppl 1:S171-3. doi: 10.1016/j.legalmed.2009.01.076. Epub 2009 Feb 28.
Immunostaining for beta-amyloid precursor protein (APP) is widely recognized as an effective tool for detecting diffuse traumatic axonal injury (TAI). APP selectively labels injured axons, such as axonal bulbs and varicose axons. However, it has been reported that axonal bulbs are detected in cases of cerebral hypoxia without head injury. Therefore, we examined whether there are differences in the morphological pattern of axonal bulbs between trauma and hypoxia. Sections of the corpus callosum from 25 cases of head injury and 23 control cases were immunostained for APP. APP staining detected axonal bulbs in 14 cases of head injury, who survived more than several hours, although it failed to label axons in control cases. In addition, two patterns of immunoreactivity were identified in several cases of head injury. The first pattern showed that labeled axons were oriented along with white matter bundles; the second demonstrated that the axons were scattered irregularly. The first pattern alone was found in 5 of 14 cases, while cases of the second pattern alone were not observed. Both patterns were detected in 5 cases and in the remaining 4 cases, clear patterns were not found. From these findings, we speculated that the first pattern may represent TAI. Further examinations are required for determining whether these two patterns are identical with patterns of trauma and hypoxic brain damage as indicated by [Oehmichen M, Meissner C, Schmidt V, Pedal I, König HG, Saternus KS. Axonal injury--a diagnostic tool in forensic neuropathology? A review. Forensic Sci Int 1998;95:67-83] and [Graham DI, Smith C, Reichard R, Leclercq PD, Gentleman SM. Trials and tribulations of using beta-amyloid precursor protein immunohistochemistry to evaluate traumatic brain injury in adults. Forensic Sci Int 2004;146:89-96].
β-淀粉样前体蛋白（APP）免疫染色被广泛认为是检测弥漫性创伤性轴索损伤（TAI）的有效工具。APP可选择性标记受损轴突，如轴突球和曲张轴突。然而，有报道称在无头部损伤的脑缺氧病例中也能检测到轴突球。因此，我们研究了创伤和缺氧情况下轴突球的形态模式是否存在差异。对25例头部损伤病例和23例对照病例的胼胝体切片进行APP免疫染色。APP染色在14例存活数小时以上的头部损伤病例中检测到轴突球，而在对照病例中未能标记轴突。此外，在几例头部损伤病例中发现了两种免疫反应模式。第一种模式显示标记的轴突与白质束平行排列；第二种模式表明轴突不规则散布。14例中有5例仅出现第一种模式，未观察到仅出现第二种模式的病例。5例同时出现两种模式，其余4例未发现明确模式。基于这些发现，我们推测第一种模式可能代表TAI。需要进一步研究以确定这两种模式是否与[Oehmichen M, Meissner C, Schmidt V, Pedal I, König HG, Saternus KS. Axonal injury--a diagnostic tool in forensic neuropathology? A review. Forensic Sci Int 1998;95:67-83]和[Graham DI, Smith C, Reichard R, Leclercq PD, Gentleman SM. Trials and tribulations of using beta-amyloid precursor protein immunohistochemistry to evaluate traumatic brain injury in adults. Forensic Sci Int 2004;146:89-96]所指出的创伤性和缺氧性脑损伤模式相同。
