Pharmaceutical Cell Line Development
Stable, High-Yield Mammalian Producer Cell Lines
Our in-house cell line engineering platform enables us to provide our clients with pharmaceutical producer clones that exceed the limits of the current industrial standard, while still supporting a royalty-free fee-for-service business model.
At ProBioGen we have built a fully integrated technology platform that encompasses the key actuating variables: Host Cell Line, Vector Technology and clone-adapted Media Platform.
Host Cell Line(s)
Adapted host cell lines are the key to optimal producer clone development and later process performance. Chinese Hamster Ovary (CHO) cells are the most common cells applied in commercial production of biopharmaceuticals. The original CHO cell line isolated in the 1950s gave rise to a range of genetically different progeny, such as K1-, DukX B11-, DG44- cell lines and others. The choice of CHO cell line can affect target protein quality and achievable yield. Therefore, ProBioGen uses two different starter cell lines, CHO-DG44 and CHO-K1, both of which have been selected for most efficient growth in chemically defined media and for optimized biopharmaceutical manufacturing.
For products which require manufacturing in human cells, our fully documented, GMP compliant Human Neuronal Precursor (AGE1.HN®) cell line is an available, alternative cell substrate. It supports specific and complex glycostructures (highly sialylated, highly branched) and provides a system for the production of glycoproteins and antibodies that require specific posttranslational modifications or suffer from instability or susceptibility for proteolysis.
The vector for transgene expression has to be matched with the particular type of adapted host cell line.
ProBioGen’s vector technology is based on sophisticated transgene and codon optimization in conjunction with carefully harmonized expression cassettes. This type of transgene optimization, cassette design and assembly routinely results in a rapid identification and isolation of top performing producer clones. Stringent double selection results in a reduced number of clones, thereby minimizing screening workload and project timelines.
Our unique expression vectors are equipped with human and viral composite promoter elements that render the promoters resistant to epigenetic silencing and make them independent from cell cycle control. This and other unique features of our vector enable the development of producer clones with exceptional clone stability even in the absence of selection reagents. Our carefully selected expression vector elements and fine-tuned transfection and drug selection procedures assure the reproducible and reliable generation of high producer clones.
We have taken great care to avoid third party rights, allowing us to offer exceptional business terms and royalty-free producer clones to our clients.
The cell culture medium containing a balanced formulation of all relevant nutrients, vitamins and trace elements is the third pillar of successful Cell Line Development.
Our proprietary chemically defined media platform supports all phases of the cell line development process including transfection, selection, sub-cloning and banking of the generated producer clones. The in-house media platform allows us to perform single cell cloning, screening and clone evaluation under conditions that mimic the manufacturing conditions at a larger scale. This provides added robustness to the overall development process.
GMP-production processes for powders and liquid media have been implemented at two different qualified media producers to ensure supply chain independence for our clients.
Certain products require unique posttranslational modifications that can only be supported by genetically engineered clones. In addition, clone engineering with regard to the expression and secretion machinery addresses the ever increasing need for higher product yield.
Our GlymaxX® clone metabolic engineering technology for example enables the production of antibodies with specialized glycan structures.
Key Advantages of ProBioGens Production Cell Lines:
Our cell lines achieve predictable and stable high mAb-expression levels in the 1–4 g/L range (non-optimized fed batch). Multi-chain proteins such as monoclonal antibodies require fine-tuned subunit expression to allow an optimal complex assembly and optimal utilization of cellular energy. Our antibody expression cassettes thus employ fine-tuned promoters and other genetic regulatory elements to support a perfectly balanced and synchronized subunit expression.
Upstream Performance and Scalability
Key upstream performance parameters (qp, IVCD, titer) remain consistent during upscale. The value of a candidate clone typically becomes apparent once it is used in a regulated fermentation process at process development scale. Miniaturized bioreactors are used for simultaneous processing of large clone numbers to analyze the clones' process properties. This "Bioreactor Performance Analysis" (BPA) is of high predictive value and assures maintenance of clone performance up to large-scale fermenters.
ProBioGen's producer clones maintain a consistently stable and high transgene expression level throughout the duration of the manufacturing time window. Our producer clones maintain their high level of transgene expression for at least 80 population doublings while being cultured in the absence of selection pressure.
The documentation for our production clones addresses all aspects covered in the relevant guidelines (ICH-Harmonized Tripartite Guidelines, EMA/FDA Points to Consider and Notes for Guidance) and contains submission-ready data to be included in the "body of data" section 3.2 of Module 3, CTD. Relevant Guidelines include ICH-Q5B (CPMP/ICH/139/95), ICH-Q5D as well as the FDA’s Points to Consider on Nucleic Acid Characterization and Genetic Stability and the TSE Note for Guidance on minimizing the risk of transmission (EMA410/01).