Stable Cell Line Development
Stable cell lines for Biologics require higher expression level and stability. We started with the Freedom CHO-S System licensed from Invitrogen to build up expression constructs and generate cell lines. In order to obtain the best expression clones, we optimized the expression construct and developing procedure.
Highlights
We enhanced the selection efficiency. | The vector from Freedom CHO-S used two selection markers in one vector, which significantly enhanced the clone selection efficiency. However, there are still large percentage of clones that express very little target proteins. We further enhanced the selectivity by reducing the selection marker activity in order to increase specificity. |
We optimized the signal peptide. | exonbio builds several expression constructs with several different signal peptides. These constructs were tested in transient expression and the best construct for your needs will be used for stable cell line development. |
Selection strategy optimized. | Although a fast cell line development process is a contingent factor for a majority of customers, we place quality of the cell line as the utmost important measure of exemplary service. We understand the needs of the customer and have optimized the cell line development procedure to focus on obtaining the highest quality expression clones. We combined two limited dilution cloning steps into one limited dilution cloning as the Freedom kit suggested; we screen the individual clones before amplification so therefore only best clones were amplified. |
For no biologics cell line development (link) we use a different system that is faster and less expensive.