【摘要】 目的:探讨树突状细胞(dendriticcells,DC)是否参与脑缺血损伤过程及在缺血脑组织中DC的来源。方法:用线栓方法封闭大鼠右侧大脑中动脉制作动物模型。用免疫组化方法检测脑缺血1h到第6天时,缺血脑DC(OX62+)的存在,以及胶质细胞/巨噬细胞(OX42+)转化成DC(OX62+),同时检测活化后的DC样细胞表达主要组织相容性复合分子Ⅱ(MHCⅡ)情况。结果:脑缺血半球和假手术半球比较,在1hDC数量增加(t=7.143,P<0.001),在脑缺血组中,缺血脑半球与非缺血脑半球比,DC的数量也增多(t=4.968,P<0.01)。脑缺血第6天缺血组与假手术组进行比较,DC表达MHCⅡ(OX62+OX6+)显著差异,每100mm2脑组织切片中OX62+OX6+细胞数量比为(53±3)比(33±2)个(t=2.975,P<0.05)。脑缺血半球在1h到第6天OX42+转变成OX62+OX42+细胞逐渐增加,脑缺血第6天脑缺血半球与非缺血半球比t=9.875,P<0.001。脑缺血损伤面积与以每100mm2脑组织片为单位的OX62+数量呈正相关(R2=0.8914,P<0.001)。结论:脑缺血后,脑缺血组织中DC的数量增加,DC数量增加与脑伤面积呈正相关,提示DC参与了脑缺血过程,大鼠脑缺血后从胶质细胞向DC样细胞转化是脑内DC的来源之一。更多还原

【Abstract】 AIM:To explore whether dendritic cells(DC) participate in cerebral ischemic process and the origin of DC in ischemic lesions.METHODS:All experimental rats had the right middle cerebral artery occlusion(MCAO) by thread occlusion method.Immunohistochemisty was used to detect DC(OX62+), microglia/macrophage(OX42+) that transformed into DC,and activated DC-like cells expressing major histocompatibility complex Ⅱ(MHCⅡ) in brain hemispheres.RESULTS:Levels of DC were elevated at 1 hour in the ischemic hemispheres versus sham hemispheres(t=7.143,P< 0.001),and the ischemic versus nonischemic hemispheres(t=4.968, P< 0.01).Activated DC expressing MHCⅡ(OX62+OX6+) were still elevated at 6 days after MCAO in the ischemic hemispheres versus sham hemispheres[(53±3) vs (33±2) per 100 mm2 brain tissue] (t=2.975,P< 0.05).Microglia transformed into DC as shown with an increase of OX62+OX42+cells in the cortex at 6 days after MCAO in the ischemic versus nonishemic hemispheres(t=9.875,P< 0.001).The area of brain lesion was positively correlated with the number of OX62+per 100 mm2 brain tissue section (R2=0.891 4,P< 0.001).CONCLUSION:Increased amount of DC in the brain after MCAO has positive correlation with brain lesion area, indicating that DC plays a role in cerebral ischemia. Microglia transformed into DC-like cells were one of the origins of DC after MCAO.更多还原