One-Pot Assay Based on CRISPR/Cas13a Technology for HEV RNA Point-of-Care Testing

Hepatitis E virus (HEV) poses a serious threat to both public health and animal food safety, thereby highlighting the demands for rapid, sensitive, and easy-to-use detection. This study aimed to develop a One-Pot assay using CRISPR/Cas13a for detecting HEV RNA, suitable for point-of-care testing (POCT) in resource-limited settings. CRISPR/Cas13a combined with reverse transcription polymerase chain reaction (RT-PCR) and reverse transcription recombinase-aided amplification (RT-RAA) was applied to a One-Pot assay device. Additionally, a large cohort of HEV-infected patient (154) and animal (104) specimens was utilized for validation. The RT-PCR/RT-RAA + CRISPR/Cas13a assays for HEV RNA detection (genotypes: HEV-1, HEV-3, and HEV-4) were established, optimized, and validated, achieving a limit of detection (LoD) of 1 copy/μL and 100% specificity. In the application validation for HEV infection, the positive rates of the RT-PCR + CRISPR and RT-RAA + CRISPR assays were 98.6% and 89.6% for patients, and 96.6% and 88.8% for animals, respectively, which were superior to those of RT-qPCR. Furthermore, sample rapid lysis, reagent lyophilization, and the One-Pot device were integrated to construct a One-Pot assay with an LoD of 10² copies/μL. Despite slight decreases in sensitivity, the One-Pot assay significantly reduces the assay time to 35 min, making it easy to perform, minimizing contamination, and meeting the requirements for screening. We developed a One-Pot assay of HEV RNA using the CRISPR/Cas13a which effectively realizes a POCT test and maximizes the impetus for POCT implementation and shows potential as a valuable tool for detecting and monitoring HEV infection.