Overall, we significantly reduced resource requirements and substantially shortened cell line development timelines by optimizing
a proprietary cell culture medium, MTCM, for all upstream process phases including transfection, amplification, subcloning,
banking, and production. Medium changes are some of the most influential factors affecting the heterogeneity of cell populations
with respect to post-translational or secondary modifications. Integrating medium screening into the process as early as the
clone selection step focuses process development efforts, not only on deriving high productivity clones, but also on maintaining
comparable biochemical profiles of the molecule for desired therapeutic potency.11
Using a single cell culture medium from early-stage cell line development all the way through high-titer production significantly
affected the process development strategies to obtain stable, robust production cell lines and high yielding cell culture
processes. It allows for more predictable feed streams for downstream processes and enables an efficient integration of process
technologies.12 It also leads to effective regulatory strategies by supporting economical processes starting at early clinical phase production.
ALAHARI ARUNAKUMARI, PhD, is the senior director of process development and the corresponding author, XIAO-PING DAI, PhD, is the assistant director of bioprocess development, JOEL GOLDSTEIN, PhD, is the associate director of transfectoma development, CLAUDIA KLOTH, PhD, is the senior manager of upstream process validation, bioprocess development, HAILE GHEBREMARIAM is the assistant director, cell line development, GLENN MACISAAC is a scientist II, cell line development, and MELISSA WAGNER is a scientist I, cell line development, all at Medarex Inc., Bloomsbury, NJ, firstname.lastname@example.org
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