A paper-based HPV E7 oncoprotein assay for cervical precancer detection at the point of care

Cervical cancer, while preventable through screening and treatment of cervical precancer, remains a global challenge with a disproportionately high burden of disease in resource-limited settings, especially in low- and middle-income countries (LMICs). Lack of affordable, easy-to-use screening and diagnostic tests contributes to this disparity. Most commercially available tests are not appropriate for use in LMICs due to resource constraints. Specifically, HPV mRNA and oncoprotein tests that have high specificity for cervical precancer and cancer require complex sample preparation protocols and expensive instrumentation. To address these limitations, an HPV E7 oncoprotein assay for HPV16, 18, and 45 was developed that is appropriate for use at the point of care. The assay is paper-based, involves only five simple steps, and does not require instrumentation. A clinically relevant limit of detection was demonstrated with cellular samples. Additionally, clinical performance was demonstrated with a small pilot study (n = 19), in which the HPV E7 paper-based assay was found to have 95% accuracy when compared to histopathologic diagnosis of cervical intraepithelial neoplasia grade 2 or more severe (CIN2+). With further clinical validation, this assay could enable highly specific point-of-care testing for cervical precancer and cancer that is instrumentation-free, affordable, and ideal for use in resource-limited settings.