Analytical performance of newly developed multiplex human papillomavirus genotyping assay using Luminex xMAP™...

Regional differences in human papillomavirus (HPV) genotypes and the presence of mixed HPV infections may affect adversely the efficacy of the HPV vaccine. Therefore, a simple and high-throughput HPV genotyping system is required. Recently, a novel HPV genotyping kit (the Mebgen™ HPV kit) was developed. This kit uses multiplex PCR and Luminex xMAP™ technology to detect 13 types of high-risk HPVs and an internal control in a 96-well format. In the present study, the analytical performance of the kit was examined using HPV plasmid DNA. All 13 types of HPVs were detected with a minimum detection sensitivity of 250 copies/test, and highly specific signals were observed. HPV 16 plasmid was detected in samples containing mixtures with other HPV-type plasmids in ratios ranging from 1:1 to 1:1000. No cross reactivity was observed with DNA from 27 types of other infectious microbes. A clinical evaluation was carried out using cervical samples from 356 patients with persistent abnormal smears diagnosed at mass public health screenings for cervical cancer. The samples were preserved in Tacas™ medium until analysis. HPV was detected in 162 (45.5%) samples including 110 (67.9%) with single infections and 52 (32.1%) with multiple infections. The type distribution of the 13 high-risk HPVs was as follows: 28.4% HPV 16, 11.7% HPV 18, 6.8% HPV 31, 3.1% HPV 33, 3.7% HPV 35, 9.3% HPV 39, 1.9% HPV 45, 8.6% HPV 51, 37.0% HPV 52, 9.3% HPV 56, 16.7% HPV 58, 3.7% HPV 59, and 1.9% HPV 68. To evaluate sample stability over time, changes in the detection of HPV DNA derived from HeLa and SiHa cells were measured in 3 types of liquid-based cytology media. HPV DNA was detected in Tacas and Thinprep™ samples after storage at 4°C or 30°C for 4 weeks and within 1 week of collection in Surepath™ samples. These results suggest that this newly developed HPV genotyping kit is suitable for use in both clinical applications and large-scale epidemiological studies.