阿尔茨海默病患者脑内CD44的表达

Expression of CD44 antigen in brains of patients with Alzheimer′s disease

目的观察ＣＤ４４阿尔茨海默病患者（ＡＤ）抗原在非痴呆老年人（ＮＤ）及脑内的表达，揭示ＣＤ４４与ＡＤ病理机制之间存在的关系。方法采用免疫组织化学（ＩＨＣ）方法检测ＣＤ４４、β淀粉样蛋白（βＡＰ）在５例ＡＤ，６例ＮＤ大脑皮层、海马、小脑等部位的表达。结果发现ＣＤ４４在１１例脑内白质的部分星形胶质细胞上存在特异性表达，但在ＡＤ皮层的灰质也存在一些表达；ＡＤ组与ＮＤ组相比，ＣＤ４４阳性度明显增加（Ｐ＜０．０１）。在ＡＤ组，新皮层、海马较小脑等部位的ＣＤ４４表达增强（Ｐ＜０．０１）；ＡＤ组脑内ＣＤ４４阳性度与βＡＰ阳性度存在相关（ｒ＝０．６７９），但两者阳性区分布欠一致。结论ＣＤ４４阳性度星形胶质细胞可能参与ＡＤ的病理机制。

Objective To observe the expressions of CD44 antigen in the brains of the patients with Alzheimer disease (AD) and non dementia (ND) and to reveal the role of CD44 in the pathogenesis of AD. Methods Using immunohistochemistry (IHC) technology, we checked up the expression of CD44 and β amyloid protein (β AP) in the cerebral cortexes, hippocampi and cerebellums of 11 cases of postmortem autopsy brain tissues.Among them, there were 5 cases of AD and 6 cases of ND. Results CD44 was specifically expressed in the astrocytes in white matters of the 11 brains. There were a lso some expressions of CD44-positive astrocytes in the gray matters of the AD cases. The expressions of CD44 in AD were significantly stronger than those in ND ( P < 0.01). In AD, the expressions of CD44 of the cerebral cortexes and hippocampi were stronger than those of the cerebellums ( P <0.01). There was correlation between the positive degrees of β AP and CD44 in the brains of AD ( r =0.679), but significant difference existed in the distributions of them. Conclusion The CD44-positive astrocytes might participate in the pathogenesis of AD.