Field-Applicable Loop-Mediated Isothermal Amplification for the Detection of Seven Common Human Papillomavirus Subtypes

Persistent HPV infection is a major risk factor for the subsequent development of cervical cancer. LAMP is simple and suitable for field detection in the resource-limited settings. In this study, hydroxy naphthol blue (HNB)-based visual LAMP and evagreen-based fluorescent LAMP coupled with a microfluidic chip (LAMP-chip) were established for the field detection of seven subtypes of HPV. The analytical sensitivity was 19-233 copies/reaction. The overall clinical sensitivity was 97.35% for visual LAMP and 98.23% for LAMP-chip. Both LAMP assays exhibited 100% specificity and were completed in less than 50 min. Additionally, both assays did not require complicated nucleic acid extraction and purification steps. A complete quality control monitoring system (including internal control, positive quality control and negative control) in the LAMP assays further ensured the credibility of the results. Our findings demonstrated that the proposed LAMP assays have the potential to be applied in the testing of common HPV DNA in field investigations (visual LAMP) or within communities and primary health centers (LAMP-chip).