Continuous insect cell (Sf-9) culture with aeration through sparging

Area of Science:

• Biotechnology
• Cell Culture Engineering
• Insect Cell Technology

Background:

• Traditional spinner flasks often face limitations with low cell density at high working volumes.
• Optimizing continuous culture conditions for insect cell lines like Spodoptera frugiperda (Sf-9) is crucial for research and bioproduction.

Purpose of the Study:

• To investigate the continuous growth of Spodoptera frugiperda Sf-9 cells in a 250-ml spinner flask.
• To evaluate the impact of air sparging and agitation on cell density and culture stability.
• To demonstrate the utility of the spinner flask for long-term, serum-free continuous culture.

Main Methods:

• Culturing Sf-9 cells in a 250-ml jacketed spinner flask with direct air sparging.
• Operating the culture at various dilution and air sparging rates under steady-state conditions.
• Utilizing a serum-free medium for extended culture maintenance.

Main Results:

• Achieved high cell density at 90% working volume, surpassing fermentor cultures.
• Demonstrated stable culture conditions (cell size, metabolic activity) at different dilution and sparging rates.
• Maintained Sf-9 cells for over 4 months in continuous culture without loss of recombinant protein expression.

Conclusions:

• The investigated spinner flask design effectively supports high-density continuous insect cell culture.
• Air sparging significantly enhances cell density in continuous cultures, a novel approach for insect cell applications.
• Serum-free continuous culture of Sf-9 cells is feasible for extended periods, preserving recombinant protein production capabilities.