Influence of the inoculum on the production of antibodies with mammalian cells

The mouse mouse hybridoma cell line BT 376 was cultivated in T-flasks, spinner flasks (30 rpm) and in a surface-aerated loop reactor (5% CO2 in air, pH and pO(2) unregulated, 300 rpm, tip speed 1.0 m s(-1)). The aim was to determine the influence of the inoculum on the growth kinetics, viability and antibody production. For this purpose young and old cells, defined by the number of subcultivations, were used. Different procedures for the inoculation of the bioreactor, using T-flasks or a spinner flask, were applied. In addition to the online monitoring of pH and pO(2), several offline measurements were carried out (cell count, viability and antibody concentration). In the bioreactor the specific growth rate of the young cells was lower (mu(6) = 0.93 d(-1), mu(24) = 1.18 d(-1)), but without a difference in the maximum antibody concentration (C-6, c(24) = 100 mg l(-1)) and the volumetric production rate (Qp(6) = 17 mg l(-1) d(-1), Qp(24) = 15 mg l(-1) d(-1)). The comparison of the preparation of the inoculum in T-flasks and in spinner flasks showed no significant difference.