Tailoring Plasmid Design Based on Chain Expression in Cell Line Development for Enhanced Monoclonal and Bispecific...

Area of Science:

• Biotechnology
• Biopharmaceutical Manufacturing
• Molecular Biology

Background:

• Cell line development is crucial for efficient biopharmaceutical production.
• Existing strategies focus on plasmid design, host cells, and selection methods.
• Optimizing expression systems is key to overcoming manufacturing challenges.

Purpose of the Study:

• To investigate strategic expression plasmid design for enhanced productivity and quality of therapeutic proteins.
• To utilize transposon technology in Chinese Hamster Ovary (CHO) cells.
• To address challenges in producing structurally complex therapeutic molecules.

Main Methods:

• Employing transposon technology for gene integration in CHO cells.
• Manipulating light and heavy chain copy numbers within expression plasmids.
• Comparing single-plasmid versus multi-plasmid strategies for complex molecules.
• Assessing the impact of additional gene copies on under-expressed chains.

Main Results:

• Increased copy numbers of light and heavy chains, with balanced expression, improved productivity and reduced purity risks.
• Consolidating all molecular chains into a single plasmid significantly enhanced both productivity and purity.
• Adding an extra copy of an under-expressed chain effectively improved purity for imbalanced molecules.
• Demonstrated a workflow for customized plasmid design and pool development.

Conclusions:

• Strategic plasmid design, including copy number control and consolidation of genetic elements, is vital for high-yield, high-purity biopharmaceutical production.
• Transposon-based systems offer a powerful platform for optimizing CHO cell lines for complex therapeutic proteins.
• The proposed workflow can increase success rates in developing cell lines for challenging molecular structures.