Demand for cell line development (CLD) is currently growing at a double-digit compound annual growth rate according to the Global Market Report 2022-2030. There is an increasing demand for bispecific and monoclonal antibodies (mAbs), recombinant proteins, and vaccines. However, CLD is a technical and operationally difficult task. CDMOs offer the latest techniques and technical experts prepared to tackle these complex projects while discovering ways to shorten your timelines. In this blog, we will detail the steps we take to accelerate timelines and decrease wait times to a master cell bank.
Transfection to RCB
To start the CLD process we thaw our in-house DG44 CHO cell line, transfect it with the DNA of interest, and create a stable transfection pool for 2 main purposes. The first is inoculating production models in shaker flasks, so we can evaluate the titer of product quality. The second is single-cell cloning, which is needed for generating monoclonal cell lines. We continue through the transfection process to determine the top 3 clone selections, once we have the final 3, we move forward to the research cell bank (RCB).
Important Milestone
This is when an important milestone in cell line development is reached. The RCB is the larger cell bank that is used to move forward as the base for the master cell bank (MCB). This milestone is important to timelines because there is a time-consuming list of workflows that follow RCB generation: sequencing the gene of insert, conduct a stability study (the prolonged seed train where we use our RCBs, passage them, and then evaluate their titer capacity), and then we use standard RCB release testing in order to grant production in our GMP facilities.
Standard vs. Accelerated Timeline
In a standard timeline, you see a long period for a stability study which is not easily changed. Activities associated with shortening this timeline are the activities that go before the RCB generation. One example of the steps we look to evaluate and shorten is the cloning expansion step. A standard industry process includes time-consuming and laborious workflows. In order to accelerate our timelines, we seeded a fixed amount of cells into different plate formats, waited 7 days, and then counted them to stimulate a cell expansion standard workflow. By utilizing this method, we save 2 weeks and minimize handling, decreasing the risk of contamination.
Decreased Wait Times
Another challenge that is faced when developing an accelerated timeline is the wait times. To decrease wait times, we bank our top clones in the RCB as early as possible and in the meantime conduct the quality analysis. These velocity activities allow us to shorten our RCB timelines from 12 weeks to 8 weeks, allowing us to provide a MCB within 20 weeks. Overall, this means we have a platform that we can offer customers that will provide them with a drug substance in 12 months.