Production of biopharmaceuticals from CHO cells requires generation of master-, working- and post-production cell banks of high quality, partly under GMPconditions. An optimal cryopreservation strategy is needed for each newproduction cell line, particularly with regard to the desire to establishproduction processes that are completely devoid of serum or even any animalcomponents and to ensure robust thaw performance for reliable production. Herewe describe a novel strategy employing flow cytometric (FC) analysis ofAnnexin V-stained cells for high-throughput characterization of CHO cellbanks. Our data show that this method enables evaluation of a cryopreservationprocedure just 6h after thaw.
