荧光定量PCR测定原发性干燥综合征患者血浆循环DNA及其临床意义

目的：荧光定量PCR测定原发性干燥综合征（pSS）患者血浆循环游离DNA（cfDNA），分析其在疾病中的意义。方法选用人类基因组管家基因TaqMan？ GeneExpression Assays：ABI 4331182，ID：Hs02758991-g1，采用PCR水解探针模式（Taqman探针）测定pSS及正常对照组中血浆cfDNA的值，同时测定pSS患者血沉（ESR）、C反应蛋白（CRP）、免疫球蛋白（IgA、IgG、IgM），并评定pSS的活动指数（SSDAI）和损害指数（SSDDI），分析cfDNA与疾病活动之间的关系。结果pSS组cf DNA浓度值为（380.64±259.10）μg/L，正常对照组cfDNA浓度值为（32.02±16.39）μg/L，两者比较差异有统计学意义（P〈0.05）；pSS组中：cfDNA浓度与SSDAI呈正相关（r=0.533， P〈0.01），与SSDDI无相关性（r=0.051，P〉0.05），SSDAI与SSDDI呈正相关（r=0.412，P〈0.01），pSS组以SSDAI值中位数4分为2组，31例pSS （SSDAI≥4）的cfDNA浓度值（509.70±215.57）μg/L，35例pSS（SSDAI〈4）的cfDNA浓度值（262.65±186.35）μg/L，两组比较差异有统计学意义（P〈0.01）。结论血浆cfDNA在pSS患者中升高，与干燥综合征疾病活动性相关，血浆cfDNA可作为PSS疾病活动的观察指标。

ObjectiveTo detect plasma circulating cell-free DNA levels of patients with primary Sjogren＇s syndrome with real-time fluorescent quantitative PCR,and investigate its clinical significance in groups of primary Sjogren＇s syndrome（pSS）and disease activity.MethodsThe primer was designed by human genome housekeeper gene TaqMan GeneExpression Assays：ABI 4331182,ID：Hs02758991_g1,Levels of cfDNA,erythrocyte sedimentation rate（ESR）,C-reaction protein（CRP）and immunoglobulin（IgA,IgG and IgM）in pSS group were detected. Meanwhile,the pSS activity index and damage index of diseases were assessed,and the relations between cfDNA and disease activity were analyzed.ResultsThe levels of plasma cfDNA in pSS group（380.64±259.10）μg/L were apparently higher than those in normal control group （32.02±16.39）μg/L,and the differences were significant statistically（P〈0.05）. In pSS group：cfDNA level was positively correlation with SSDAI（r=0.533,P〈0.01）.But there was no correlation between cfDNA concentration and SSDDI（r=0.051,P〉0.05）;pSS group were divided into 2 groups by SSDAI median value of 4,the cfDNA level of 31 cases of pSS（SSDAI≥4）was（509.70±215.57）μg/L,the cfDNA level of 35 cases of pSS（SSDAI 〈4）was（262.65±186.35）μg/L,and the difference was statistically significant（P〈0.01）.Conclusions The cfDNA is increased in group of pSS,and it is positively correlated with SSDAI;It can be used as one of the disease activity indices of pSS.