High-throughput mAb expression and purification platform based on transient CHO.

Area of Science:

• Biotechnology
• Biopharmaceutical Manufacturing
• Protein Engineering

Background:

• High-cell-density transient transfection systems are crucial for rapid monoclonal antibody (mAb) production.
• Existing methods require optimization for high-throughput parallel processing and purification.

Purpose of the Study:

• To develop and validate a high-throughput system for producing purified monoclonal antibodies (mAbs) using transient transfection.
• To couple high-yield transient transfection with semiautomated protein A purification for drug discovery.

Main Methods:

• Utilized a CHO-GS-KO cell line for high-cell-density transient transfection in 24-deep-well plates.
• Implemented a semiautomated protein A purification process using a Biomek FX(p) liquid handling robot for up to 72 unique mAbs.
• Optimized batch-binding and variable volume elution strategies to maximize mAb recovery and concentration.

Main Results:

• Achieved monoclonal antibody titers up to 350 mg/L in a 7-day process.
• Successfully purified >0.25 mg of mAb at >0.5 mg/mL without concentration steps.
• Produced 56 affinity maturation mAb variants with an average yield of 0.33 mg and 42 unique early-stage mAbs with an average yield of 0.79 mg.

Conclusions:

• The integrated system of parallel high-yielding transient transfection and semiautomated purification is a valuable tool for mAb drug discovery.
• This approach enables efficient, simultaneous expression and purification of numerous unique monoclonal antibodies.
• Optimized purification steps are critical for maximizing both recovery and concentration of purified mAbs.