Development of new cell factories for manufacture of biopharmaceuticals

The Chinese Hamster Ovary (CHO) cell platform is the cornerstone for manufacture (bioprocessing) of recombinant protein-based medicines (biopharmaceuticals) of immense commercial and societal value. A pivotal consideration across the bioprocessing sector is the drive to develop the capabilities for manufacture of novel emerging biopharmaceuticals (bi-/tri-specific antibodies, modular domain fusion-based synthetic proteins, fragment-engineered mimetics). Such (next-generation) medicines present the major strand for the development pipeline (and are 60-70% of new entities) but these brilliantly imagined, but non-natural, "proteins" challenge the synthetic and secretory capabilities of host cells used to express "natural" antibodies, hormones and growth factors. The Dickson laboratory has several industrial collaborations investigating molecular loci that limit the production of biopharmaceuticals of "difficult to express (DTE)" categorisation. This provides the context for the proposed collaborative project between Dickson and FDB. The derivation of CHO cells means they are heterogeneous and populations contain clones that are genetically, epigenetically and phenotypically distinct. Consequently, individual clones have distinctive functional properties - in terms of growth, robustness, secretory capability, processing and quality control of secretory proteins. The heterogeneity within CHO cell populations has been used in directed evolution to derive cell lines with desirable functional properties for manufacture. FDB have developed a series of clones via such evolutionary processes that have extensive variation in functional properties for use as manufacturing hosts. The general aim of this project is to examine the FDB-derived clones, using the complementary technologies of the Dickson laboratory, to provide a molecular framework that indicates how the genetic and phenotypic diversity of CHO cell populations can be used to provide product- and process-specific systems for manufacture of the next generation of biopharmaceuticals. These data and the lessons from their interpretations will also be used to enhance the efficiency of bioprocessing of existing products and processes.
Specific objectives
- CHO cell clones (FDB) will be characterised in terms of their effectiveness as hosts for the production of a training set of exemplar recombinant proteins (growth and production in different media/feed conditions, production of antibodies and DTE proteins with assessment of protein quality)
- Clones that exhibit desirable protein- and process-specific properties (productivity and quality) will be characterised in terms of transcriptome (RNAseq), proteome (SWATH) and metabolome (GC-MS, LC-MS) and the resultant data will be interrogated to extract predictive relationships between cellular functionality and molecular profiling
- Predictive interpretation will be tested by expression of "unknown" recombinant proteins in a product-type and process-type ranking of specific clones. The data obtained will be used to define genome editing approaches to stably re-engineer desirable geno/phenotype to host cells