Patent ID: 8178318

Claim:
A method for enhancing product yield in a mammalian cell culture process comprising the steps of: agitating a cell culture medium in a bioreactor using an upward flowing impeller disposed below a top surface of the cell culture medium in the bioreactor; adjusting the volumetric flow of an oxygen containing sweep gas in a headspace above the top surface of the cell culture medium in the bioreactor during a growth phase and a production phase of the mammalian cell culture process to maintain the concentration of dissolved oxygen in the cell culture medium in an optimum range for the mammalian cells through surface gas exchange at the top surface of the cell culture medium in the bioreactor and to maintain the dissolved carbon dioxide in the cell culture medium at a level of less than about 10% concentration of dissolved carbon dioxide throughout the growth phase and the production phase of the mammalian cell culture process by removing dissolved carbon dioxide through surface gas exchange at the top surface of the cell culture medium in the bioreactor; wherein the osmolality in the cell culture medium is maintained in an optimum range for the particular cells during the mammalian cell culture process and the pH of the cell culture medium is maintained in an optimum range for the particular cells during the mammalian cell culture process.