Visual detection of human metapneumovirus using CRISPR-Cas12a diagnostics

Area of Science:

• Molecular Biology
• Virology
• Biotechnology

Background:

• Human metapneumovirus (HmPV) is a significant cause of respiratory tract infections.
• Accurate and rapid diagnostic tools are crucial for managing HmPV outbreaks.
• Existing diagnostic methods may lack the speed or accessibility required for widespread clinical use.

Purpose of the Study:

• To develop a novel, rapid, and sensitive detection technique for human metapneumovirus (HmPV).
• To combine reverse transcription recombinase polymerase amplification (RT-RPA) with CRISPR-Cas12a for enhanced diagnostic capabilities.
• To evaluate the performance of the developed RT-RPA-Cas12a assay in clinical settings.

Main Methods:

• Designed and evaluated four primer pairs targeting the nucleoprotein (N) gene of HmPV.
• Employed RT-RPA for amplifying HmPV genetic material.
• Utilized CRISPR-Cas12a for detection of amplified products, coupled with fluorescence or lateral flow (LF) readouts.
• Assessed specificity against common respiratory viruses and evaluated performance on 28 clinical samples.

Main Results:

• The RT-RPA-Cas12a assay achieved a detection limit as low as 6.97 × 10^2 copies/mL.
• Assays completed within 35 minutes (fluorescence) or 45 minutes (LF) with no cross-reactivity observed.
• Clinical sample analysis showed high coincidence rates with quantitative RT-PCR (96.4% for fluorescence, 92.9% for LF).

Conclusions:

• The developed RT-RPA-Cas12a-based assay offers high sensitivity and specificity for HmPV detection.
• The method provides rapid results suitable for clinical diagnosis.
• The assay's ease of use and minimal equipment requirements suggest significant potential for widespread clinical application.