生物素亲和素系统在ECP的实验效能

目的:评估生物素亲和素系统检测嗜酸性粒细胞阳离子蛋白(ECP)双抗夹心ELISA试验中的应用。方法:建立直接包被抗体的检测法、先包被生物素的检测法和先包被亲和素的检测法,比较3种方法的灵敏度、不准确度和变异度,并用3种方法检测皮肤病患者和正常对照人群的ECP水平。结果:直接包被抗体的ECP检测法线性范围为2.5~200μg/L,灵敏度为2.75μg/L,不准确度为11.5%;先包被生物素的检测法线性范围为2.5~500μg/L,灵敏度为2.61μg/L,不准确度为10.9%;先包被亲和素的检测法线性范围为2.5~500μg/L,灵敏度2.68μg/L,不准确度为11.9%;3种方法的重复性差异无统计学意义;先包被亲和素的检测法最稳定,直接包被抗体的检测法次之,先包被生物素的检测法最不稳定;3种方法及ADL双抗夹心检测试剂盒检测患者及正常对照者血清ECP水平,差异无统计学意义。结论:生物素亲和素包被可提高实验的灵敏度、线性范围,减少抗体用量,节约抗体包被时间。

The Application of Biotin-Avidin System in Double-Antibody Sandwich ELISA Method for Eosinophilia Cationic Protein

Objective:To evaluate the effect of biotin-avidin system (BAS) on the experimental performance of the sandwich enzyme immunoassay of double antibodies kit (ELISA) for eosinophilia cationic protein (ECP). Methods: The direct detection of antibody-coated, detection of biotin-coated first and detection of avidin-coated first methods were established. The sensitivity,inaccuracy and variability were compared between three methods. The levels of ECP were detected using these three methods in patients with skin diseases and control subjects . Results: The linear range, sensitivity and relative deviation of direct coating were 2.5-200 μg/L, 2.75 μg/L and 11.5%,respectively. The linear range, sensitivity and inaccuracy of biotin coating test were 2.5-500 μg/L, 2.61 μg/L and 10.9%, respectively. The linear range, sensitivity and relative deviation of avidin coating test were 2.5-500 μg/L, 2.68 μg/L and 11.9%, respectively. There was no significant difference in reproducibility between three methods. The avidin coating test was the most stable method, and followed the antibody coating test. The biotin coating test was the most unstable method. The serum levels of ECP were detected by the three detected methods and ADL ECP kit in patients and control subjects. Conclusion: Biotin-avidin coating can elevate the linear range and sensitivity of the test, and which could reduce antibody dosage and antibody coating time.