Abstract:

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 albicans. 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 μg/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 albicans, and has shown a satisfactory sensitivity and specificity in the animal model experiment.