PROCESS DEVELOPMENT IN SCREENING SCALE BIOREACTORS AND PERSPECTIVES FOR VERY HIGH CELL DENSITY PERFUSION

摘要

Intensified perfusion is recognized as an attractive technology for the production of biopharmaceuticals. This renewed interest for perfusion creates new questions. Which cell density, productivity and process should be targeted? What are the challenges? How to develop these processes? We address these questions for Chinese Hamster Ovary cells (CHO) and Human Embryonic Kidney HEK293 cells. We have developed parallel screening systems, which are real mimics of very high cell density perfusion bioreactors achieving 80 to 100 x 10~6 cells/mL and operated at < 250 mL. With these systems, we have studied several aspects such as feeding regime optimization and its influence on the glycosylation and shear stress by flow filtration, supported as well by transcriptomics. The shear stress created by the cell separation systems Alternating Flow Filtration (ATF) and classical Tangential Flow Filtration (TFF) are different and can be limiting for more sensitive cells such as HEK293 cells. We will review our results and put them in the perspective of perfusion intensification.