脑干星形细胞胶质原纤维酸性蛋白免疫组化染色的图像分析

目的探讨脑干星形细胞胶质原纤维酸性蛋白(GFAP)免疫组化染色及其图像分析在原发性脑干损伤鉴定中的应用价值。方法26例原发性脑干损伤致死者的脑干样本,分别在其中脑、脑桥及延脑相同部位取组织作GFAP免疫组化染色(LSAB法),并对GFAP阳性物最密集视野做图像分析。21例非颅脑损伤或脑部病变死亡者的脑干作对照样本,所得图像参数测量值进行统计学分析。结果(1)对照组星形细胞的GFAP阳性染色在中脑、脑桥及延脑三个部位分布不等(P<0.05),延脑>中脑>脑桥;损伤组则三个部位无显著性差异(P>0.05);(2)对照组与损伤组相比,GFAP阳性染色细胞的数量在中脑、脑桥及延脑等三个部位中差异均有显著性(P<0.01);(3)死后96h后解剖者,损伤组与对照组有显著差异;(4)伤后30min内死亡者,损伤组与对照组也有显著差异。结论人脑干星形细胞GFAP免疫组化染色的图像分析,对法医学鉴定原发性脑干损伤具有重要参考价值。

Image analysis of GFAP expressed astrocytes in the subjects with primary brainstem injury

Objective To investigate the value of GFAP expression in astrocytes for the diagnosis of primary brain stem injury. Methods The tissue sections taken from midbrain, pons cerebelli and medulla oblongata of 26 subjects died from primary brainstem injury were stained with GFAP immunohistochemistry by LSAB method. Nine microscopic view-fields with aggregated GFAP positive substance were selected for image analysis. Meanwhile, 21 subjects died from non-brain injury or other brain diseases were enrolled as a control group. Statistical analysis was adopted for comparing the image parameters between the two groups.Results (1) In the control group, the positive GFAP astrocytes were distributed irregularly among the 3 parts. The quantity of GFAP positive cells in medulla oblongata was greater than that of midbrain, and the quantity of which was also greater than that of pons cerebelli as well, P<0.05. However, in the injury group, there was no significant difference among the 3 parts, P>0.05. (2) The quantities of GFAP positive astrocytes were also significantly different between the injury group and control group, whether they were in midbrain, pons cerebelli or medulla oblongata (all P<0.01). (3) Irrespctive of the samples taken from the subjects having died 96 hours or died within 30 minutes after injury, the results were the same, that is to say, they were different statistically between the injury group and the control group.Conclusion The overexpression of GFAP in human brainstem astrocytes and the analysis of their image parameters could be used as early diagnostic indicators for brainstem injury. This technique has meaningful value in identifying acute injury for primary brainstem injury in forensic medicine.