ISSN:
0178-515X
Source:
Springer Online Journal Archives 1860-2000
Topics:
Process Engineering, Biotechnology, Nutrition Technology
Notes:
Abstract In this work, metabolite and antibody production kinetics of hybridoma cultures were investigated as a function of cell density and growth rate in a homogeneous perfusion reactor. Hydrophilized hollow fiber polypropylene membranes with a pore size of 0.2 μm were used for medium perfusion. Oxygen was supplied to the cells through thin walled silicone tubing. The mouse–mouse hybridoma cells were grown in three identical bioreactors at perfusion rates of 1.1, 2.0, and 3.2/day for a period of eight days during which the viable cell concentrations reached stable values of 2.6×106, 3.5×106, and 5.2×106 cells/ml, respectively. Total cell densities reached values ranging from 8×106 to 1×107 cells/ml. Specific substrate consumption and product formation rates responded differently to changes in cell density and apparent specific growth rate, which were not varied independently. Using multiple regression analysis, the specific glucose consumption rate was found to vary with viable cell density while the specific glutamine uptake and lactate production rates varied with both viable cell density and apparent specific growth rate. These results suggest that cell density dictates the rate of glucose consumption while the cell growth rate influences how glucose is metabolized, i.e., through glycolysis or the TCA cycle. The specific antibody production rate was found to be a strong function of cell density, increasing as cell density increased, but was essentially independent of the specific growth rate for the cell line under study. List of Symbols MAb monoclonal antibody X v viable cell density (cells/ml) X d nonviable cell density (cells/ml) μ specific growth rate (1/day) k d specific death rate (1/day) D dilution rate (1/day) S f substrate concentration in feed (g/l or mM) S substrate concentration (g/l or mM) P f product concentration in feed (g/l or μg/ml) P product concentration (g/l or μg/ml) q s specific consumption rate of substrate (g/hr/cell or mmol/hr/cell) q p specific production rate of product (g/hr/cell) q MAb specific production rate of monoclonal antibody (μg/hr/cell)
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00387697
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