系统性红斑狼疮患者及其家庭成员外周血基因表达谱的研究

Gene Expression Profiles of Peripheral Blood in a Family with Systemic Lupus Erythematosus

目的研究家族性SLE患者、一级亲属和正常人外周血基因表达谱的改变,探讨家族性SLE发病机制。方法首先从外周血提取总RNA,逆转录合成单链、双链cDNA后,体外转录合成生物素标记的cRNA与基因芯片进行杂交,再通过抗原抗体反应机制标记上荧光染料Cy3后,使用基因芯片扫描仪进行图像扫描。使用分析软件进行表达差异和聚类分析。结果在3000多个基因中,鉴定出59个基因存在表达差异,其中有34个基因表达上调,25个基因表达下调,这与散发性SLE患者的表达差异基因基本相同。在34个表达上调基因中,有22个基因在SLE患者和其未患病的姐妹中都表达上调;在25个表达下调的基因中,有17个基因在SLE患者和其未患病的姐妹中都表达下调。聚类分析显示根据外周血基因表达谱可明确地将SLE患者、未患病亲属及正常人对照区分开。结论该基因芯片技术有较高的重复性和稳定性,能有效地进行家族性SLE疾病相关基因的初步筛选。

Objective To investigate the pathogenesis of familial systemic lupus erythematosus (SLE), by analyzing the gene expression profile of peripheral blood in a family with 2 SLE patients and their first-degree relatives. Methods Total RNA was extracted from peripheral blood cells of normal subjects and SLE patients. Then, synthesis double strand cDNA template from total RNA, transcription of cRNA probe with Biotin labeling, hybridization of probe with Microarray, binding of Streptavidin to Biotin, amplification with First Antibody, further amplification with Cy3-Conjugated Second Antibody, detection of Cy3 dye with ScanArray 5000 were performed. With QuantArray microarray analysis software, the scan image information was converted into numeric data. With GeneSpring microarray analysis software, cluster analysis was done to find interested genes. Results Over 3000 target genes were analysed. Fifty-nine genes differentially expressed in familial SLE patients and controls were identified. Among them, 34 genes were up-regulated and 25 genes were down-regulated. These differentially expressed genes identified in two familial SLE patients were almost identical to those found in other sporadic SLE patients. Among 34 expression increasing genes, 22 were up-regulated in SLE sisters and unaffected sisters; among 25 expression decreased genes, 17 genes down-regulated in SLE sisters and unaffected sister. Cluster analysis showed that patients were clearly separated from controls and their unaffected sisters based on their gene expression profile. These results showed that in familial SLE, multiple genes were responsible for susceptibility to SLE, and clinically unaffected relatives shared some lupus susceptibility genes with their clinically affected relatives, in addition environmental factors were probably necessary to trigger disease. Conclusion These results indicate that high-density oligonucleotide microarray has the potential to explore the heredity in SLE families.