A high fidelity CRISPR/Cas12a based lateral flow biosensor for the detection of HPV16 and HPV18

Abnormal growth of uterine cervix cells may eventually lead to cervical cancer, which is mainly associated with the two most prevalent types of Human Papilloma Virus (HPV), namely HPV16 and HPV18. Cervical cancer can be prevented or treated owing to its slow progression. Therefore, its early, fast, and sensitive diagnosis is crucial. Herein, we developed an ultrasensitive approach for HPV16 and HPV18 detection based on a combination of loop-mediated isothermal amplification (LAMP), CRISPR-Cas12a trans-cleavage propensity and lateral flow biosensor (LFB), collectively termed CIALFB (CRISPR/Cas-Isothermal Amplification based LFB). CIALFB is characterized by Cas12a-mediated trans-cleavage of the reporter ssDNA upon target recognition, which results in undetectable LFB test line signal. This method was highly sensitive to detect 3.1 attomoles (∼1.8 copies) of the target, and reliably specific to detect both virus types from clinical samples with various HPV strains. Our system possesses the potential to detect other infectious diseases without tedious DNA extraction and handling, and expensive apparatuses.