Systematic Evaluation of Vector Sequence Elements in Isogenic CHO Cells for Improved Antibody Production

Area of Science:

• Biotechnology
• Molecular Biology
• Bioprocessing

Background:

• Monoclonal antibodies (mAbs) are vital biotherapeutics, necessitating efficient manufacturing.
• Predictable and high-yield mAb production is hindered by vector element variability.

Purpose of the Study:

• To investigate how specific DNA sequence design features affect mAb expression in a CHO system.
• To identify key sequence elements for optimizing mAb production and quality.

Main Methods:

• Evaluated codon usage in constant regions (CL, CH) with and without Fc mutations.
• Assessed impact of signal peptide type and variable region codon optimization.
• Compared expression using kappa vs. lambda light chains in CHO cells.

Main Results:

• Suboptimal codons in CL/CH reduced expression regardless of Fc mutations.
• Signal peptide changes yielded antibody-specific productivity effects.
• Variable region codon optimization enhanced productivity significantly (2-18 fold).
• Kappa light chain generally outperformed lambda in CHO cells.

Conclusions:

• Sequence engineering principles for CHO expression include codon optimization and appropriate signal peptides.
• CHO cell preference for kappa light chain impacts productivity.
• These findings aid in selecting constructs for high-yield mAb production.