GoldMag^? Particles-Based Acridinium Ester-Chemiluminescence Immunoassay For Detection Of Human Epididymis Protein 4

Human epididymis protein 4(HE4) expression level is low in normal tissue cells, but is high in tumor tissues, especially in ovarian serous carcinomas. As a new ovarian cancer marker, HE4 has a higher sensitivity than carbohydrate antigen-125(CA125), the widely-accepted ovarian cancer marker at present. In clinical, although HE4 has a relatively high content in the serum of ovarian cancer patients, we still need a more sensitive method to be able to accurately detect the low level of HE4 which would help the early diagnosis of ovarian cancera.Objective To develop a GoldMag(?) particle-based magnetic chemiluminescence immunoassay for HE4 and evaluate it. Methods We took the GoldMag(?) paticles as the solid-phase carrier, and the acridinium ester (AE) as the chemiluminescence agent to label the HE4 detection antibody. The HE4 quantitative detection system was established based on the double-antibody sandwich principle and the acridine ester(AE)-H2O2 chemiluminescence reaction system. Linear range, sensitivity and precision were evaluated in this study. Concentrations of HE4 in 65 clinical human serum specimens were determined by two different methods:the GoldMag(?) particle-based magnetic chemiluminescence immunoassay established in this study, and the commercialized electro chemiluminescence immunoassay kit from Roche. Results This method had a good linear relationship between 0.3 ng/mL and 25 ng/mL(R2=0.9976) with the detection limit of 0.069 ng/mL. The intra-assay precision was less than 10% and the inter-assay precision was less than 15%. In the contrast experiment of 65 clinical human serum specimens, the results obtained using the method established in this study showed a high correlation and consistency with the method of electro chemiluminescence immunoassay kit from Roche. Conclusion HE4 detection antibody has been conjugated to acridinium ester successfully, and the GoldMag(?) particle-based magnetic chemiluminescence immunoassay for HE4 has been developed, which lays the foundation for HE4 clinical detection.