Galasko D
Department of Neurosciences (Neurology), University of California, San Diego, USA.
J Neural Transm Suppl. 1998;53:209-21.
CSF levels of proteins related to the lesions of Alzheimer's Disease (AD) may be informative. These include the microtubule-associated protein tau, an integral component of neurofibrillary tangles, and A beta, a 4kDa protein that accumulates in senile plaque amyloid. Many studies have found that CSF tau is increased in AD compared to normal controls (NC). CSF tau may be increased in a minority of patients with destructive neurological disorders or several neurodegenerative conditions, making its use in differential diagnosis less clear. CSF tau consists of fragments that lack extensive phosphorylation. CSF levels of A beta species ending at residue 40 are unchanged in AD. However species ending at residue 42 (A beta 42) are significantly decreased in AD compared to NC. Decreased A beta 42 may be found in patients with other dementias, some of whom may harbor AD pathology. Simultaneous measurement of CSF A beta 42 and tau may improve discrimination between AD and NC, and may facilitate the diagnosis of early stage AD.
与阿尔茨海默病（AD）病变相关的脑脊液蛋白质水平可能具有参考价值。这些蛋白质包括微管相关蛋白tau（神经原纤维缠结的主要成分）以及β淀粉样蛋白（一种在老年斑淀粉样物中积聚的4kDa蛋白质）。许多研究发现，与正常对照（NC）相比，AD患者脑脊液中的tau蛋白增加。在少数患有破坏性神经系统疾病或几种神经退行性疾病的患者中，脑脊液tau蛋白也可能升高，这使得其在鉴别诊断中的应用不太明确。脑脊液tau蛋白由缺乏广泛磷酸化的片段组成。在AD患者中，以第40位氨基酸残基结尾的β淀粉样蛋白种类的脑脊液水平没有变化。然而，与NC相比，AD患者中以第42位氨基酸残基结尾的β淀粉样蛋白种类（Aβ42）显著降低。在患有其他痴呆症的患者中也可能发现Aβ42降低，其中一些患者可能存在AD病理特征。同时检测脑脊液中的Aβ42和tau蛋白可能会提高AD与NC之间的鉴别能力，并有助于早期AD的诊断。
