白念珠菌芽管特异性抗原快速检测方法的建立和初步评价

Establishment and preliminary evaluation of a rapid detection method for germ tube-specific antigensof Candida albicans

目的建立白念珠菌芽管特异性抗原快速检测系统，探讨其特异性和敏感性。方法以单克隆抗体McAb03．2C1-C2作为一抗，辣根过氧化物酶标记McAb03．2C1-C2为二抗，建立双抗体夹心ELISA实验方法并检测6只动物模型和5例系统性白念珠菌感染患者的血清标本。结果筛选出McAb03．2C1-C2最佳稀释度和检测包被抗原浓度分别为l：4000和1．25-40μg,／ml；双抗体夹心ELISA检测动物模型的特异性和敏感性分别为95％、92％，其对阳性临床标本的检测结果与常规鉴定方法一致。结论初步建立白念珠菌芽管特异性抗原的双抗体ELISA快速检测系统，动物模型实验证实该系统有较好的特异性和敏感性。

Objective To establish a double-antibody sandwich enzyme linked immunosorbent assay （DAS-ELISA） for the rapid detection of germ tube-specific antigens of Candida albicans, and to evaluate its specificity and sensitivity. Methods A DAS-ELISA was established with the monoclonal antibody McAb03.2C1-C2 as the primary antibody, and horseradish peroxidase （HRP） labeled McAb03.2C1-C2 as the secondary antibody. The established assay was used to detect germ tube-specific antigens of Candida albicans in sera from 5 patients with systemic Candida albicans infection and from 6 rabbit models at 12, 24, 48, 72 hours, on week 1, 2 after infection with Candida a/b/cans. Results A good liner relationship was observed between the absorbance value at 495 nm and antigen concentrations when the titer of McAb03.2C1-C2 was 1 ： 4000 and the concentration of coated antigen varied from 1.25 to 40 txg/ml. The specificity and sensitivity of the DAS-ELISA were 95% and 92% respectively in the detection of germ tube-specific antigens in the rabbit models. The results of detection with DAS-ELISA in serum specimens from the patients were consistent with those with the routine method. Conclusions A DAS-ELISA is primarily established for the rapid detection of germ tube-specific antigens of Candida a/bicans, and has shown a satisfactory sensitivity and specificity in the animal model experiment.