慢性粒细胞白血病ssDNA适配子检测方法的评价

Evaluation of detection method for chronic myeloid leukemia cell ssDNA aptamer

目的评价慢性粒细胞白血病(chronic myeloid leukemia,CML)ssDNA适配子检测方法的临床诊断应用价值。方法基于前期构建的方法,用ssDNA适配子与K562细胞及临床CML标本结合进行检测,在优化的检测条件下,以美国临床实验室标准化组织(Clinical and Laboratory Standard Institude,CLSL)的相关标准为依据,对该方法进行方法学评价,并对方法进行临床诊断性能的评价。结果建立的方法回归方程为:y=1 476.4+495.31 x,r2=0.976 6,拟合度较高;该方法敏感性较高,特异性较强,检测高、中、低浓度的K562细胞的批内变异系数均小于5%,日间变异系数均大于5%;该方法测得的不同浓度CML标本的总平均回收率为78.7%;测得的溶血、黄疸及血脂标本的平均干扰率均>10.0%;ROC曲线下面积为0.867,ssDNA适配子检测CML组、非慢粒类型白血病组、健康对照组标本的敏感度为75%,特异度为77%,阳性似然比为3.26,阴性似然比为0.32,漏诊率为25%,可靠度为0.306,可用度为0.52。结论 CML ssDNA适配子检测方法本身灵敏度高,检测阈值低,特异性强;在临床诊断性能研究中,该方法特异性高,但敏感性较低,具有一定的临床诊断价值。但该方法抗干扰能力弱,重复性较差,且可靠度<0.5,其临床应用还有一定的局限性。

Objective To evaluate the significance of detection method for chronic myeloid leukemia （CML） cell ssDNA aptamer in clinical diagnosis. Methods Based on method developed previously, ssDNA aptamer was combined with K562 cells and clinical specimens of CML. Under the optimized condition, the method was evaluated for methodology and clinically diagnostic performance according to the relevant standard developed by the Clinical and Laboratory Standard Institute （CLSL）. Results The regression equation of the developed method was as follows： y = 1 476.4 ＋ 495. 31 x, rz = 0. 976 6, indicating a high goodness of fit. The method showed high sensitivity and specificity, by which the intra- CV of detection results of K562 cells at high, moderate and low concentrations was less than 5%, while the inter-CV was more than 5%. The total mean recovery rate of clinical CML specimens at various coneentrations detected by the method was 78. 7%, while the mean interference rates of specimens for hemolysis, jaundiee and blood-lipid were more than 10. 0%, with an area under curve（AUC） of 0. 867. The sensitivity of ssDNA aptamer in deteetion of specimens in CML, non-CML and healthy control groups was 75%, while the specificity was 77%, the positive likelihood ratio was 3. 26, the negative likelihood ratio was 0. 32, the misdiagnosis rate was 25%, the reliability was 0. 306, and the availability was 0. 52. Conclusion The developed method showed high sensitivity, low detection threshold value, and high specificity. The study on clinically diagnostic performance showed high speeificity but low sensitivity of the method. However, low an- ti-interference ability, low reproducibility and reliability of less than 0. 5 limited the clinical applieation of the method.