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Updated: Aug 11, 2025
Author Spotlight: Development of Simplified CRISPR-Based Tests for Rapid Detection of Infectious Diseases
Published on: August 16, 2024
An extraction-free one-step CRISPR-assisted detection platform and a potential Streptococcus pneumoniae at-home
Xiaotong Qiu1, Xueping Liu2, Ruixue Wang3
1State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.
Abstract:
A rapid, accurate, easy-to-use nucleic acid detection technology is essential for disease diagnosis and control. Herein, we improved CRISPR-top (cluster regularly interspaced short palindromic repeats-mediated testing in one-pot) to develop Extraction-free one-step CRISPR-assistant detection (ExCad), a simple, rapid, accurate gene detection tool for unextracted colonies and samples. We established a pretreatment protocol to rapidly liquify sputum samples and release nucleic acids within 10 min. The ExCad results can be visualised by a real-time fluorescence reader or the naked eye under blue light. We developed an ExCad-Sp assay to detect Streptococcus pneumoniae from unextracted strains and specimens, and optimised the assay conditions. Assay feasibility was evaluated using sputum samples from 32 patients, and it achieved 92.9 % (13/14) sensitivity, 100 % (18/18) specificity, 100 % (13/13) positive predictive value, and 94.7 % (18/19) negative predictive value compared with bacteria culture. The ExCad-Sp assay has potential for developing an at-home self-testing kit for S. pneumoniae.
