Analysis of Xinjiang HPV16 L1 gene polymorphisms: a newly developed, low-cost enzyme-linked immunosorbent assay

Xinjiang, China shows the world's highest incidence and mortality rates of cervical cancer. Due to limited conditions available for medical examination, hybrid capture 2 (HC2) and other detection methods are used rarely, and early screening for human papillomavirus (HPV) cannot be carried out. Therefore, we established a double-antibody sandwich (DAS)-enzyme-linked immunosorbent assay (ELISA) based on a polymorphism of the Xinjiang HPV16 L1 strain (KU721788). According to the conserved sequence and specific epitope of Xinjiang strain HPV16 L1, we prepared two anti-HPV16 L1 monoclonal antibodies and combined them to construct a DAS-ELISA. Detection conditions for the DAS-ELISA were optimized, and HC2 was used as the control to verify the specificity, repeatability and coincidence detection of the DAS-ELISA. The optimized conditions for the DAS-ELISA were: dilution of the capture antibody was 1:100; the enzyme-labelled antibody was 1:10; the sample reaction time was 45 min; the enzyme-labelled antibody was applied for 40 min, and the substrate color development time was 15 min. The quality of the DAS-ELISA for the detection of HPV 16 was very high, and there was no significant difference when compared with HC2. The DAS-ELISA developed on the basis of the Xinjiang strain (KU721788) polymorphism possesses the advantages of a detection rate similar to that for the HC2 assay currently used clinically, but it is more convenient operationally and at lower cost. DAS-ELISA is thus easier to implement for cervical cancer screening in economically depressed areas.