ISSN:
1573-0778
Keywords:
HEK 293
;
packed bed bioreactor
;
perfusion
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
,
Process Engineering, Biotechnology, Nutrition Technology
Notes:
Abstract The extracellular domain of human parathyroid Ca2+ receptor was needed in order to study itsstructure and clinical application. The Ca2+receptor is a unique member of the G protein-coupledreceptor super-family, expressed in parathyroid andkidney cells where it has been shown to play acritical role in extracellular calcium homeostasis.The desired protein was produced by immobilizing thetransformed HEK 293 cells in a packed-bedconfiguration using a 1.6 l (working volume)bioreactor equipped with a vertical mixing impellerassembly and an internal basket. The process includeda propagation phase followed by a production phase. Inthe propagation phase, lasting approximately 160 h, the bed was perfused with a serum-containingmedium, allowing the cells to grow at a constantgrowth rate to approximately 3 × 1010. At this point the production phase was begun, replacing themedium with serum-free medium and continuing theperfusion process for additional 350 h. Duringthis phase, the medium was pumped through the packedbed at a rate of 4–6 l per day, keeping theresidual glucose concentration around 1 g l-1 andcollecting and processing approximately 80 l ofspent medium. This continuous perfusion method of thepacked-bed bioreactor was compared to a repeated batchmethod in which existing medium was replenished whenthe glucose concentration was down to 1 g l-1. Using this method, serum-free medium was replaced withserum containing medium a few times when a decline inthe glucose consumption was observed. Though mediumconsumption and protein yield are similar in bothmethods (roughly 10 mg l-1), there aredifferences related to the ease of operation andprocessing of the produced protein. The continuousperfusion operation was found to be preferable and waschosen as the production strategy.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1008143132056
Permalink
