Determination Of Host Cell DNA & Fragment Size Distribution By Quantitative Real-Time PCR

Ensuring the safety and efficacy of biologics requires rigorous monitoring of residual host cell DNA (hcDNA), a common byproduct of the manufacturing process. Because hcDNA can carry infectious or oncogenic risks, regulatory bodies like the FDA and EMA mandate strict limits, often restricting concentrations to 10 ng per dose. Particular attention is paid to DNA fragments longer than 200 base pairs, as these are large enough to potentially harbor functional genes.

Quantitative real-time PCR (qPCR) has emerged as the industry standard for this analysis, offering a broader working range and higher sensitivity than alternative methods. By utilizing duplex PCR and internal extraction controls, laboratories can simultaneously quantify target DNA and assess fragment size distribution across multiple species, including Vero, human, and bovine cells. This validated approach ensures that even at concentrations as low as 0.0015 ng/mL, residual DNA is accurately detected to maintain full regulatory compliance.