Quantitative detection of t(14;18)-positive cells by real-time quantitative PCR using fluorogenic probes

Area of Science:

• Molecular Biology
• Oncology
• Genetics

Background:

• The t(14;18) translocation is a hallmark of follicular lymphoma.
• Accurate detection of t(14;18)-positive cells is crucial for molecular staging and monitoring minimal residual disease.

Purpose of the Study:

• To establish an automated, real-time quantitative PCR assay for detecting t(14;18)-positive cells.
• To evaluate the sensitivity, reproducibility, and advantages of this new assay compared to conventional methods.

Main Methods:

• Development of a real-time quantitative PCR assay using double-labeled fluorogenic probes.
• Validation using known copy numbers of t(14;18)-positive genomic DNA.
• Analysis of peripheral blood mononuclear cells (PBMNC) from follicular lymphoma patients using both real-time PCR and a two-step semi-nested PCR with limiting dilution.

Main Results:

• The real-time PCR assay demonstrated high reproducibility for initial copy numbers ranging from 10 to 10(5).
• Single-copy detection was confirmed using a stochastic multiple-tube approach.
• Quantitative results from real-time PCR correlated well with those from the two-step PCR method.
• The assay offers advantages including fewer critical pipetting steps, reduced time, and built-in contamination control.

Conclusions:

• Real-time quantitative PCR provides a sensitive, specific, and reproducible method for detecting t(14;18)-positive cells.
• This assay is valuable for molecular staging, detecting minimal residual tumor cells, and epidemiological studies.
• It is particularly useful for analyzing blood stem-cell preparations for transplantation.