Services
Process development and scale-up for mammalian cells
General cell culture process development and assessment of scale-up potential. Among other tasks, optimization of growth and production media can be offered, as well as a thorough analysis of growth rate, sub-cultivation ratio, highest attainable cell mass under given culture conditions, specific and volumetric productivity using productivity enhancing conditions. Also, a scale-down model can be applied that predict performance of cells and process under scale-up conditions for an envisioned production facility for manufacturing. To do this work a novel proprietary and highly predictive high through-put system for the rapid assessment of process steps will be employed.
Rapid protein production (mg-g) from mammalian cells
We offer rapid gene expression applying our proprietary CHO and HEK-293 derived host cell lines. These cells have been optimized for efficient DNA uptake and high protein expression and grow to high density in suspension cultures. Rapid productions can be executed in operation scales from the ml to the 100 liter bioreactor. Product(s), i.e. harvested cell culture fluids or recovered protein, can be delivered to the client within 4 weeks after an appropriate expression vector has been constructed. ExcellGene offers the possibility to clone the client's gene constructs into our own superior (typically 5-10fold better than client constructs) vectors.
Generation and optimization of stable mammalian cell lines for recombinant protein synthesis
Cell line development for production purposes. The entire work, comprising of transfection, selection and isolation of clonal cell populations, evaluation of primary clones for productivity, adaptability for growth in serum-free suspension culture, long-term production stability and scalability to bioreactors is offered. Also, if required, gene amplification using methotrexate and subsequent cloning and banking can be done. As an essential part, studies on genetic and productive stability in the presence and absence of selective agents can be executed. Banking of cell populations as prebanks, masterbanks or working cell banks can be offered.
Vector construction and improvement for high efficiency expression from stable cell lines or for transient expression
Vector construction for stable or transient protein synthesis in mammalian cells. Cloning of cDNA constructs into mammalian expression vectors, useful for high level productivity both for stable and transient expression is offered. If necessary and wished, addition of secretory signals or tags into expression vectors to facilitate eventually recovery through affinity chromatography can be part of this work. Also, more elaborate constructs can be envisioned which link the expression of the desired gene, gene-fragment or fusion-construct with the expression of a fluorescent protein, such as GFP. Generation and identification of high productivity stable cell lines, ready for scale-up and cGMP production.
Protein recovery and purification
If requested, product can be recovered from cell culture supernatants or from cell harvests (if protein remains within cells). Standard recovery processes are applied, based on client provided information on the protein of interest.
Consulting
Consulting on mammalian cell culture processes, scale-up to manufacturing scale, availability and costing of cGMP manufacturing options. Also, consulting on typical requirements for the regulatory approval process for clinical products can be offered.
