In conclusion, we have developed, and will continue to develop, tools to increase our understanding of, and continuously improve,
our expression systems, our cell line development practices, and our outcomes. This manuscript has described how certain of
these tools have enabled us to better understand, and specifically cope with, cell line instability. Using these tools has
enabled the earlier identification of unstable clones, which is critical given our aggressive development timelines. In addition,
given the industry-wide movement toward using more efficient practices during the development of protein therapeutics, our
ability to predict cell line instability, and to invest time and resources on only those clones that are viable candidates,
is beneficial. Finally, the information and learnings that result from using these tools and assays will continue to be key
in eliminating instability altogether, thus enabling improved consistency and predictability of cell lines in our future projects.
ROBIN HELLER-HARRISON is the associate director and the corresponding author, KERSTIN CROWE is a research scientist II, CECILIA COOLEY is a research scientist I, MEGAN HONE is scientist II, KEVIN MCCARTHY is a principal scientist I, and MARK LEONARD is the director, all in the cell and molecular sciences group in the department of Drug Substance Development at Wyeth BioPharma,
Andover, MA, 978.247.1406, RHHarrison@wyeth.com
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