趋化因子在重症继发性肺结核患者表达研究

Expression of chemokine in severe secondary pulmonary tuberculosis patients

目的对基因表达谱芯片筛选出的重症比对轻症继发性肺结核患者基因CCL3、CCL4、CXCL2进行验证,探索其表达下调与重症继发性肺结核免疫病理机制的关系。方法用Affymetrix基因表达谱芯片检测重症和轻症继发性肺结核患者以及与健康对照相比的差异表达基因;用real-time PCR法测定重症、轻症患者和健康对照CCL3、CCL4、CX-CL2的相对表达量;用方差分析和非参数检验统计方法判断组间比较的统计学意义。结果表达谱芯片筛选出重症继发性肺结核患者有大量差异表达基因,一些免疫基因表现为下调,可能与病变严重程度有相关性。real-time PCR结果显示CCL3在重症vs轻症表达下调(P<0.05),重症vs健康有下调趋势;CCL4在组间比较虽无统计学差异但重症vs轻症、重症vs健康有下调表达趋势;CXCL2在重症vs轻症有下调趋势,相对于健康人有轻度上调(P<0.05)。结论基因表达谱芯片检测CCL3、CCL4、CXCL2在重症vs轻症继发性肺结核患者表达下调,验证结果与芯片基本相符,趋化因子下调可能在重症继发性肺结核免疫病理机制中有重要作用。

Objective To verify the expression levels of chemokines（CCL3,CCL4,CXCL2）which were down-regulatedin severe vs mild secondary tuberculosis（TB） patients according to gene expression profiling analysis and to investigate thecorrelation between down- regulated expression of chemokines and immunopathology mechnism in severe secondary TB.Methods The differently expressed gene was detected by Affymetrix expression profile gene chip. The relative transcriptlevels of chemokines（CCL3,CCL4,CXCL2） were assayed by real time-PCR in severe, mild secondary TB cases and healthycontrols. ANOVA and non- parametric tests were used for statistic analysis among the groups. Results A mount ofdifferential gens were selected by gene expression profile chip. Some immune genes were down- regulated and it might berelated to the severity of disease. The results of RT-PCR verified that the expression of CCL3 was down-regulated in severe vsmild secondary TB patients（P〈0.05）and the trends was down-regulated in severe secondary TB vs healthy controls.There wereno statistic significant difference among groups for CCL4,but the trends was down-regulated in severe vs mild secondary TBand in severe secondary TB vs healthy controls. The trends of CXCL2 expression showed down-regulated in severe vs mildsecondary TB while it was up-regulated gently in severe secondary TB vs healthy controls（P〈0.05）. Conclusion Expressionof CCL3,CCL4 and CXCL2 were down-regulated in severe vs mild secondary TB by gene expression profile analysis. Furtherverification results confirmed with the gene analysis results. The down- regulation of chemokines may involve inimmunopathology of severe secondary TB.