Cell Line Development
Reducing timelines in generating clonal cell lines for therapeutic protein production
Introduction
In order to produce high yields of recombinant proteins for therapeutic applications stable producer cell lines need to be developed. Mammalian host cell lines such as CHO or HEK 293 are typically the system of choice due to the importance of consistent post-translational modifications. To produce monoclonal antibodies (mAbs) or other therapeutic proteins a suitable host cell line is transfected with the gene of interest. This leads to random or targeted integration of DNA into the host genome. Following transfection, cells need to be isolated to derive monoclonal cell lines. Typically, a large number of such clones then need to be screened for productivity, stability, and product quality. Promising candidates are finally selected for further upscaling.
Proof of clonality
Clear and traceable evidence of single-cell dispensing
Single-cell cloning and proof of clonality
Following transfection, single cells need to be isolated from transfected pools. Traditionally, this crucial step has been performed by limiting dilution. Based on early regulatory guidelines released by the U.S. Food and Drug Administration (FDA) and others, the production cell line of recombinant products is to be cloned from a single progenitor cell in order to minimize population heterogeneity and facilitate isolation and subsequent selection of high producing clones.
Our solution
Our single-cell dispensing technology allows for deterministic single-cell isolation, offers documented image-based proof of clonality, and provides efficient and fast single-cell seeding combined with excellent cell viability and zero risk of cross-contamination.
Early suspension culture
After single-cell cloning, cells are typically cultured under static conditions for several weeks before viable clones are transferred to shaken deep well or 24-well plates. After additional cultivation, selected clones are then transferred to larger volumes and finally to shake flasks or mini bioreactors. Hence, during the first weeks after cloning, cells are cultured under static conditions, which do not match the culture environment the cells experience in later stages of the process and during production. Our innovative microbioreactor platform, the C.BIRD™™, was developed to enable suspension culture early in the cell line development process.
