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A High-throughput Automated Platform for the Development of Manufacturing Cell Lines for Protein Therapeutics
Published on: September 22, 2011
Optimization of cell line development in the GS-CHO expression system using a high-throughput, single cell-based
Tsuyoshi Nakamura1, Takeshi Omasa2
1Institute of Technology and Science, Tokushima University, 2-1 Minamijosanjima-cho, Tokushima 770-8506, Japan; Astellas Pharma Inc., 2-5-1 Nihonbashi-Honcho, Chuo-ku, Tokyo 103-8411, Japan.
Abstract:
Therapeutic antibodies are commonly produced by high-expressing, clonal and recombinant Chinese hamster ovary (CHO) cell lines. Currently, CHO cells dominate as a commercial production host because of their ease of use, established regulatory track record, and safety profile. CHO-K1SV is a suspension, protein-free-adapted CHO-K1-derived cell line employing the glutamine synthetase (GS) gene expression system (GS-CHO expression system). The selection of high-producing mammalian cell lines is a crucial step in process development for the production of therapeutic antibodies. In general, cloning by the limiting dilution method is used to isolate high-producing monoclonal CHO cells. However, the limiting dilution method is time consuming and has a low probability of monoclonality. To minimize the duration and increase the probability of obtaining high-producing clones with high monoclonality, an automated single cell-based clone selector, the ClonePix FL system, is available. In this study, we applied the high-throughput ClonePix FL system for cell line development using CHO-K1SV cells and investigated efficient conditions for single cell-based clone selection. CHO-K1SV cell growth at the pre-picking stage was improved by optimizing the formulation of semi-solid medium. The efficiency of picking and cell growth at the post-picking stage was improved by optimization of the plating time without decreasing the diversity of clones. The conditions for selection, including the medium formulation, were the most important factors for the single cell-based clone selection system to construct a high-producing CHO cell line.
Insights
Optimizing cell culture conditions and plating times with the ClonePix FL system enhances high-producing clone selection for therapeutic antibody production using Chinese hamster ovary (CHO) cells.
Area of Science:
- Biotechnology
- Cell Line Development
- Mammalian Cell Culture
Background:
- Chinese hamster ovary (CHO) cells are the primary host for therapeutic antibody production due to their safety and regulatory approval.
- The glutamine synthetase (GS) gene expression system is utilized in CHO-K1SV cells for efficient protein production.
- Traditional limiting dilution cloning is inefficient for isolating high-producing, monoclonal CHO cell lines.
Purpose of the Study:
- To optimize the ClonePix FL system for high-throughput single-cell cloning of CHO-K1SV cells.
- To improve the efficiency and monoclonality of high-producing clone selection.
- To identify key factors influencing successful single-cell clone selection.
Main Methods:
- Application of the automated ClonePix FL system for single-cell selection.
- Optimization of semi-solid medium formulation for pre-picking cell growth.
- Adjustment of plating time for improved post-picking cell growth and efficiency.
Main Results:
- Optimized semi-solid medium formulation enhanced CHO-K1SV cell growth before picking.
- Adjusted plating times improved post-picking cell growth and selection efficiency without reducing clone diversity.
- Medium formulation and selection conditions were identified as critical for establishing high-producing CHO cell lines.
Conclusions:
- The ClonePix FL system, combined with optimized medium and plating conditions, significantly improves the selection of high-producing CHO cell clones.
- This approach enhances efficiency and monoclonality in cell line development for biopharmaceutical manufacturing.
- Optimized single-cell selection is crucial for constructing robust and productive CHO cell lines for therapeutic antibody production.
