May 8-13, 2016
For over 75 years, continuous manufacturing has been investigated in both academia and industry as an alternative to batch manufacturing. Perfusion is a well-recognized method for continuous production of biomolecules expressed in CHO cell culture and it is known to have certain advantages over batch and fed‑batch processes. The major advantage of perfusion processes is that a constant environment is provided to cells through continuous by-product removal and nutrient addition. However, it has proven to be challenging to apply high-throughput approaches routinely used in fed-batch process development while maintaining true continuous culture, and so semi-continuous methods have instead been pursued for perfusion process development. In an effort to confirm how effective each method could be for early process development or as a quick perfusion applicability test for a particular clone, a media panel consisting of ten candidates was developed. In this study, several established high-throughput small-scale models, comprising batch-refeed cultures in spin tubes (Corning® 50mL Mini Bioreactors) and two semi-continuous methods in ambr15™ microbioreactors, were applied to evaluate the performance of the perfusion media panel candidates for up to 18 days with a recombinant CHO cell line expressing IgG. Different observations resulted from the three different approaches, but in each case a simulated steady-state was achieved for several key indicators such as cell density and product titer. Best results were seen in the spin tube batch-refeed process, where a medium exchange strategy of 63% per day was used to mimic metabolic by-product removal of 1 reactor volume per day (RVD). For the spin tube method, viable cell densities up to 30 million vc/mL were observed and the highest daily IgG titer of 525 mg/L (qP ~14 pg/cell/day) was achieved with perfusion medium 6 (PM6). Additional verification studies to confirm these findings in small-scale perfusion bioreactors will also be discussed.
Yang Wang, Shawn Barrett, Borka Naumovich, Jessica Nichols, and Steve Gorfien, "Perfusion media development and evaluation with spin tube and ambr15 highthroughput small-scale models" in "Cell Culture Engineering XV", Robert Kiss, Genentech Sarah Harcum, Clemson University Jeff Chalmers, Ohio State University Eds, ECI Symposium Series, (2016). http://dc.engconfintl.org/cellculture_xv/154