High Cell Density Cultivation of Mast Cells in Fluidized-Bed and Fixed-Bed Bioreactors

Abstract

The possibihty for continuous mast cell cultivation in fluidized-bed and fixed-bed bioreactors with cell immobihzation in open porous microcarriers was investigated. Due to the higher mechanical stress in the fluidized-bed and the weak adhesion forces of mast cells, a long-term immobilization in the fluidized-bed was not possible, shown by dielectric spectroscopy. In a fixed-bed bioreactor a continuous fermentation was performed, with a steady-state cell density 38 times higher than in suspension batch cultivation. The immobihzed ceUs were continuously proHferating, analogous to the exponential growth phase in batch fermentation, proven by cell cycle analysis. An interleukin-3 concentration of 2 ng/ml has been found to be sufficient to support optimal cell growth.