Sensitive pathogen DNA detection by a multi-guide RNA Cas12a assay favoring trans- versus cis-cleavage

Most CRISPR assays lack clinical utility due to their complex workflows and limited validation. Here we present a streamlined “one-pot” asymmetric CRISPR tuberculosis assay that attenuates amplicon degradation to achieve 5 copies/μL sensitivity within 60 min and detect positive patient samples within 15 min. This assay exhibited 93%, 83%, and 93% sensitivity with adult respiratory, pediatric stool, and adult cerebral spinal fluid specimens, and detected 64% of clinically diagnosed tuberculous meningitis cases, in a cohort of 603 clinical samples. This assay achieves complete specificity and greater sensitivity (74% vs. 56%) than the most sensitive reference test with prospectively collected tongue swabs, and exhibits similar performance when adapted to a lateral flow assay format and employed to analyze self-collected tongue swabs. These results demonstrate the utility of this approach across diverse specimen types, including those suitable for use in remote and resource-limited settings, to improve access to molecular diagnostics. CRISPR-based diagnostics are often limited by complex workflows and poor validation. Here the authors develop and validate a one-pot asymmetric CRISPR assay, which permits rapid and sensitive diagnosis of tuberculosis in a format which is suitable for resource-limited settings.