目的 研究趋化因子CXCL1在重度脑外伤(TBI)患者脑组织中的细胞定位及在脑组织和血液中的表达，探讨其与损伤严重程度的关系。方法 2013年9月至2015年10月，选取重度TBI住院、且行开颅手术患者78例为实验组，所有患者均收集血液，其中19例收集到脑组织。实验组根据入院时格拉斯哥昏迷量表(GCS)评分分为重型TBI组(6~8分，n=35)和特重型TBI组(3~5分，n=43)。10例病例对照组脑组织标本来自摘除的脑血管瘤或良性肿瘤边缘少量正常脑组织。10例健康对照组血液来自同期在本院健康体检正常者。采用免疫荧光双标法检测重度TBI患者CXCL1在脑组织中的细胞定位；ELISA法检测损伤后脑组织和不同时间点血液中CXCL1蛋白的表达；Spearman相关分析对不同时间点外周血中CXCL1蛋白含量与术后30 d 格拉斯哥结局量表(GOS)评分进行相关性分析。结果 正常脑组织内CXCL1主要表达在星形胶质细胞；重度TBI后，CXCL1主要表达在神经元和星形胶质细胞。特重型TBI组CXCL1蛋白在脑组织中的含量高于重型TBI组(t=-12.58, P<0.05)。重型TBI组CXCL1蛋白在血液中含量于术前达高峰，随后逐渐下降，术后14 d仍高于健康对照组(P<0.05)，术后30 d降至健康者水平(P>0.05)。特重型TBI组CXCL1蛋白在血液中含量术前和术后1 d最高，其后逐渐下降，术后30 d仍高于健康者(P<0.05)。术前至术后30 d，特重型TBI组CXCL1蛋白含量均高于重型TBI组(P<0.05)。特重型TBI组术前血液中CXCL1蛋白含量与GOS评分呈负相关(r=-0.351, P<0.05)。结论 重度TBI后CXCL1表达明显增高，且主要表达在神经元和星形胶质细胞，同时CXCL1含量在一定程度上可以反映脑损伤的严重程度和预后。
Objective To explore the cellular localization of chemokine (C-X-C motif) ligand 1 (CXCL1) in brain tissue and its expression in brain tissue and blood in patients with severe traumatic brain injury (TBI), as well as its correlation with the injury severity. Methods From September, 2013 to October, 2015, 78 cases of TBI with craniotomy admitted to our hospital were involved as TBI group. A total of 78 peripheral blood samples and 19 brain tissue samples were studied. According to the scores of Glasgow Coma Scale (GCS) at admission, the TBI group was classified as severe TBI group (6~8, n=35) and particularly severe TBI group (3~5, n=43). Ten cases of control brain tissue were taken from patients with cerebral aneurysms or benign tumor and also undergoing craniotomy during the same time. Peripheral blood from ten healthy people were involved as the healthy control group. Immunofluorescent double staining was used to detect the cellular localization of CXCL1 in brain tissues, and ELISA was used to detect the expression of CXCL1 in brain tissue and blood. The relationship between the level of CXCL1 in peripheral blood at different time and the score of Glasgow Outcome Scale (GOS) was analyzed with Spearman correlation analysis. Results In normal brain tissue, CXCL1 mainly localized in astrocytes. For severe TBI, CXCL1 mainly expressed in neurons and astrocytes. The level of CXCL1 was higher in brain tissue in the particularly severe TBI group than in the severe TBI group (t=-12.58, P<0.05). In the severe TBI group, the level of CXCL1 in blood reached a peak before surgery, then gradually decreased, and was still higher than that in the healthy control group 14 days after surgery (P<0.05), however, no significant difference was found 30 days after surgery compared to the healthy control group (P>0.05). In the particularly severe TBI group, the level of CXCL1 in blood reached a peak before and one day after surgery, then gradually decreased, and was still higher than that in the healthy control group 30 days after surgery (P<0.05). The level of CXCL1 in blood was higher in the particularly severe TBI group than in the severe TBI group at all time points (P<0.05), and the level before surgery was negatively correlated with the score of GOS in the particularly severe TBI group (r=-0.351, P<0.05). Conclusion The CXCL1 protein of injury brain tissue was mainly colocalized in neurons and astrocytes in severe TBI patients, and the expression was associated with injury severity and outcome.
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