Buée-Scherrer V, Condamines O, Mourton-Gilles C, Jakes R, Goedert M, Pau B, Delacourte A
INSERM U422, Lille, France.
Brain Res Mol Brain Res. 1996 Jul;39(1-2):79-88. doi: 10.1016/0169-328x(96)00003-4.
Alzheimer's disease is characterized by an intraneuronal aggregation of hyperphosphorylated tau proteins into paired helical filaments. The hyperphosphorylation of tau proteins induces a decrease in their electrophoretic mobility, resulting in a pathological tau triplet referred to as tau 55, 64 and 69 or tau-PHF. We have developed monoclonal antibodies directed against this pathological tau triplet. In the present article, we report the properties of antibody AD2, which detects the hyperphosphorylated tau proteins forming paired helical filaments during Alzheimer's disease. Using immunoblotting, AD2 exclusively labeled the tau triplet, while normal tau proteins from control cases were not immunodetected. Furthermore, AD2 is highly specific in that it was able to detect the triplet not only in tau preparations but also in total brain homogenates from Alzheimer's disease patients. The binding of this monoclonal antibody to tau proteins is phosphorylation dependent. Characterization of this antibody allowed us to identify its epitope as containing phosphorylated Ser-396 with the participation of phosphorylated Ser-404. AD2 was also shown to label normal tau proteins from rapidly processed brain tissues, but its epitope is rapidly dephosphorylated during postmortem intervals. However, in autopsic brains, AD2 still represents a valuable tool to investigate neurofibrillary degeneration at the biochemical and immunocytochemical levels.
阿尔茨海默病的特征是神经元内过度磷酸化的tau蛋白聚集成双螺旋丝。tau蛋白的过度磷酸化导致其电泳迁移率降低，产生一种病理性tau三联体，称为tau 55、64和69或tau-PHF。我们已经开发出针对这种病理性tau三联体的单克隆抗体。在本文中，我们报告了抗体AD2的特性，该抗体可检测在阿尔茨海默病期间形成双螺旋丝的过度磷酸化tau蛋白。使用免疫印迹法，AD2仅标记tau三联体，而对照病例中的正常tau蛋白未被免疫检测到。此外，AD2具有高度特异性，因为它不仅能够在tau制剂中检测到三联体，还能在阿尔茨海默病患者的全脑匀浆中检测到。这种单克隆抗体与tau蛋白的结合是磷酸化依赖性的。对该抗体的表征使我们能够确定其表位包含磷酸化的Ser-396，并伴有磷酸化的Ser-404。AD2也被证明可标记来自快速处理的脑组织中的正常tau蛋白，但其表位在死后间隔期间会迅速去磷酸化。然而，在尸检大脑中，AD2仍然是在生化和免疫细胞化学水平上研究神经原纤维变性的有价值工具。
