Highly efficient inoculum propagation in perfusion culture using WAVE Bioreactor™ systems

Abstract

A perfusion-based process was developed to drastically increase the split ratio during the scale-up of CHO-S cell cultures. Fed-batch cultures were inoculated with cells propagated in either batch or perfusion cultures. All cultures were grown in disposable Cellbag™ bioreactors using the WAVE Bioreactor system. Cell concentrations of 4.8 × 10 7 cells/mL were achieved in perfusion culture, whereas the final cell concentration in batch culture was 5.1 × 10 6 cells/mL. The higher cell concentration allowed to increase the split ratio more than 6-fold to about 1:30 for inoculum propagated in perfusion culture. The method described here could reduce the number of required expansion steps and eliminate one or two bioreactors in the seed train. Disposable bioreactors with only a few liters working volume have the potential to directly inoculate volumes of up to 1000 liters. Alternatively high biomass concentrations accumulated in perfusion culture can be used to seed production bioreactors at increased cell concentrations. This would allow to shorten process time in these bioreactors, which often is the bottleneck in plant throughput.