Our Mammalian Cell Line Development platform integrates three key components:
- CHEF1® high-productivity expression plasmids
- Superior performance serum-free suspension-adapted (SFSA) CHO cells
- Custom production media
All three components of this integrated platform have been codeveloped to create optimal growth conditions that yield high cell densities, resulting in consistent, stable expression of our clients’ proteins in rapid time frames.
Technologies:
- Batch, fed-batch, and continuous operation
- Fill-and-draw, spin filter, BioSep, and ATF technology
- Two different purification lines with two to four separate suites equipped with state-of-the-art purification equipment
- Bulk lyophilization
- Class A environment for aseptic filling of drug substance
- Analysis and QP release of drug substance and drug product
- Serum-free cells and transfection
- CHEF1 expression plasmids
- Serum-free cloning and monoclonal documentation by microscopic imaging
- FACS screening: Isolation of stable, high-productivity clones
- Complete development documentation
CHEF1
The CHEF1 expression plasmid is the technological foundation of our cell line development platform. Utilizing the regulatory sequences of the Chinese hamster EF-1a (CHEF1) gene, our vectors promote constitutive high-level expression of recombinant proteins early in development. The CHEF1 system allows rapid isolation of stable CHO cell lines because gene amplification is not required to achieve high-level expression. As a result, many months of development time can be saved. CHEF1 cell lines typically produce gram quantities of protein in 7 to 8 weeks from transfection and production-quality clones in 11 to 14 weeks. A variety of CHEF1 vectors are available with different selectable markers permitting expression of heterodimeric proteins, as well as modification enzymes to improve product quality or expression levels. The CHEF1 vectors have been successfully used to create manufacturing cell lines expressing a variety of different recombinant proteins including difficult-to-express glycoproteins.
- Hamster Elongation Factor Promoter: Constitutive Expression
- Rapid Cell Line Development: No Gene Amplification
- Multiple Selectable Markers: Protein Co-expression
- Stable, Low Copy Number Integrations
- Convenient, Multiple Cloning Sites
Serum-free Cells
CMC Biologics has developed a serum-free suspension-adapted (SFSA) CHO cell line with superior cell culture performance. Our SFSA cells are propagated entirely in serum-free media and adapted to chemically defined CD-CIM1. High cell density production growth (in excess of 10 million cells per milliliter) is routinely achieved in production models. These cells are available as part of our standard cell line development platform.
FACS – Cell Screening
Manufacturing cell line development relies heavily on identification and isolation of high-expressing clones from pools of non-clonal cells. Flow cytometry is a rapid technique for primary screening and isolation of high-expressing clones, and it has the potential to greatly expedite the clone selection process. Our cell screening technologies utilize flow cytometry as part of both our standard platform and custom cell line screening projects.
Custom Services
Molecular Services
- CHEF1 vector construction
- Cell line stability and genetic characterization
- Gene sequence confirmation
Cell Line Services
- Cloning of existing client mammalian cell lines
- Characterization and expression stability of mammalian cell lines
FACS Screening Services
- Enrichment of high-producing cells in transfected CHO pool population
- Identification of high-producing CHO clones