Improving expression of recombinant human IGF-1 using IGF-1R knockout CHO cell lines

Area of Science:

• Biotechnology
• Cell Line Engineering
• Recombinant Protein Production

Background:

• Chinese Hamster Ovary (CHO) cells are essential for large-scale biopharmaceutical manufacturing.
• Expression of mutated human Insulin-like Growth Factor 1 Ea peptide (hIGF-1Ea mut) in CHO cells led to poor cell growth and low productivity (0.1-0.2 g/L).
• Human IGF-1 variants impede CHO cell growth through the IGF-1 receptor (IGF-1R).

Purpose of the Study:

• To overcome hIGF-1 mediated growth inhibition in CHO cells.
• To enhance the productivity of recombinant biopharmaceuticals in engineered CHO cell lines.

Main Methods:

• Generated IGF-1 receptor (IGF-1R) knockout (KO) CHO cell lines.
• Performed IGF-1R knockdown (KD) in a CHO cell line.
• Assessed the impact of these genetic modifications on cell growth and recombinant protein productivity.

Main Results:

• Both IGF-1R KO and KD CHO cell lines exhibited significantly reduced hIGF-1 mediated growth inhibition.
• Productivity increased by 10-fold at the pool level and 7-fold at the clone level.
• Achieved a final titer of 1.3 g/L for the recombinant biopharmaceutical.

Conclusions:

• Cell line engineering targeting IGF-1R is an effective strategy to improve yields of challenging recombinant proteins in CHO cells.
• IGF-1R modulation overcomes growth inhibition, enabling higher productivity.
• This approach offers a powerful tool for optimizing biopharmaceutical manufacturing processes.