Rapid at-line early cell death quantification using capacitance spectroscopy.

Area of Science:

• Biotechnology
• Cell Biology
• Process Analytical Technology (PAT)

Background:

• Cell death, particularly apoptosis, is a critical failure mode in mammalian cell culture, impacting productivity and product quality.
• Early detection of apoptosis is essential for implementing preventive controls in biopharmaceutical manufacturing.
• Traditional methods like trypan blue exclusion and flow cytometry have limitations in speed, labor, or early detection.

Purpose of the Study:

• To develop and validate a quantification model for measuring the percentage of apoptotic cells using capacitance spectroscopy in an at-line setup.
• To demonstrate the model's accuracy and early warning capabilities compared to conventional methods.
• To assess the scalability and transferability of the at-line capacitance spectroscopy method.

Main Methods:

• Utilized capacitance spectroscopy to capture changes in cellular properties associated with apoptosis.
• Developed a quantification model to correlate capacitance measurements with the percentage of apoptotic cells.
• Validated the model using an independent test set from bench-scale bioreactors and compared results with flow cytometry and trypan blue exclusion tests.

Main Results:

• The capacitance spectroscopy model achieved a root-mean-squared error of prediction of 8.8% on an independent test set.
• Predicted culture evolution trajectories closely matched flow cytometry measurements.
• The method detected cell death onset earlier than the trypan blue exclusion test.

Conclusions:

• Capacitance spectroscopy provides a rapid, simple, and less labor-intensive method for quantifying apoptotic cells compared to flow cytometry.
• The at-line setup is scalable and transferable across different manufacturing scales, facilitating process consistency.
• This technology enables earlier intervention for cell death, enhancing bioprocess control and product quality.