Rapid in situ mutation detection in extracellular vesicle-DNA.

Area of Science:

• Biotechnology
• Molecular Biology
• Cancer Diagnostics

Background:

• Mutation detection is crucial for cancer diagnosis and targeted therapy.
• Traditional methods like PCR and sequencing are time-consuming and require specialized equipment.
• The COVID-19 pandemic highlighted challenges in mutation analysis due to high demand for viral testing.

Purpose of the Study:

• To develop a rapid, PCR- and sequencing-free assay for DNA mutation detection.
• To utilize CRISPR-Cas12a technology for sensitive and efficient mutation quantification.
• To enable accessible cancer mutation analysis using fundamental laboratory tools.

Main Methods:

• A 30-minute DNA mutation detection technique using Cas12a-loaded liposomes.
• CRISPR-Cas12a complex and fluorescence-quenching (FQ) probes introduced into tumor-derived extracellular vesicles (EVs) via membrane fusion.
• Cas12a-mediated *trans*-cleavage of FQ probes upon target hybridization, generating fluorescence signals.

Main Results:

• Demonstrated a rapid (30-minute) DNA mutation detection assay.
• Successfully quantified DNA mutations using fluorescence signals generated by CRISPR-Cas12a activity.
• Validated the assay's potential for analyzing mutations within extracellular vesicles.

Conclusions:

• The developed assay provides a fast and accessible method for cancer mutation detection.
• This technique reduces reliance on specialized equipment, making mutation analysis more widely available.
• Future applications include multiplexing and high-throughput screening for home-based self-diagnosis and treatment monitoring.