An Ultrasensitive PCR-Based CRISPR-Cas13a Method for the Detection of Helicobacter pylori

Area of Science:

• Molecular Biology
• Infectious Diseases
• Biotechnology

Background:

• Rapid and simple detection of Helicobacter pylori (H. pylori) is crucial for effective clinical eradication.
• Existing diagnostic methods like endoscopy, histology, culture, RUT, and molecular tests have limitations in sensitivity or speed.
• There is a need for an ultrasensitive and accurate nucleic acid detection platform for H. pylori identification.

Purpose of the Study:

• To develop and validate a novel, ultrasensitive nucleic acid detection platform for H. pylori.
• To create a rapid diagnostic system combining PCR amplification with CRISPR-Cas13a technology.
• To assess the specificity and accuracy of the developed PCR-Cas13a assay against clinical strains and specimens.

Main Methods:

• Developed a novel PCR-Cas13a assay utilizing specific primers for pre-amplification and CRISPR RNA (crRNA) for detection.
• Validated the assay using DNA from 84 clinical H. pylori strains and 71 clinical specimens.
• Compared the diagnostic performance of PCR-Cas13a with traditional methods and quantitative PCR (q-PCR).

Main Results:

• The PCR-Cas13a assay demonstrated high specificity for H. pylori, distinguishing it from other common pathogens.
• Achieved a limit of detection as low as 2.2 copies/μL within 30 minutes post-PCR amplification.
• Exhibited 100% accuracy in coincidence analysis with traditional methods, 98% sensitivity, and 100% specificity compared to q-PCR, with a lower limit of detection.

Conclusions:

• The developed PCR-Cas13a system provides a highly sensitive and accurate method for H. pylori screening.
• This novel diagnostic platform offers rapid detection and distinguishes H. pylori from other pathogens.
• The PCR-based CRISPR assay shows significant potential for the detection of H. pylori and other slow-growing pathogens.