Accelerating perfusion process optimization by scanning non-steady-state responses.

Area of Science:

• Biotechnology
• Bioprocess Engineering
• Cell Culture Technology

Background:

• Perfusion cultures offer consistent conditions and high productivity but have slow process development due to long steady-state achievement times.
• Traditional optimization relies on reaching steady states, which can take over a week per condition.
• Accelerating process development is crucial for efficient biopharmaceutical manufacturing.

Purpose of the Study:

• To accelerate process development in perfusion cultures by utilizing non-steady-state transient responses.
• To qualitatively predict steady-state performance from transient data, reducing overall development time.
• To validate transient scanning as a predictive tool for optimizing perfusion culture conditions.

Main Methods:

• Implemented transient scanning by shifting temperature every 3 days (37°C down to 31°C, then up).
• Applied transient scanning to both small-scale, non-instrumented cultures and high cell density perfusion cultures.
• Investigated 1-day transient shifts to assess cellular adaptation dynamics.

Main Results:

• Transient responses qualitatively predicted steady-state performance, with higher tissue plasminogen activator (t-PA) concentrations predicted at lower temperatures.
• Transient values on day 3 showed close concordance with pseudo-steady-state values.
• Small-scale cultures yielded similar qualitative results, though with significantly lower quantitative t-PA yields.

Conclusions:

• Transient scanning effectively predicts steady-state performance in perfusion cultures, significantly reducing development time.
• The method can be applied to various scales, offering flexibility in process development.
• Combining transient scanning with pseudo-steady-state verification can decrease process development time by more than two-thirds.