HIGH-DENSITY CULTIVATION OF HYBRIDOMA IN CHARGED POROUS CARRIERS

A porous carrier whose surface is charged with polyethyleneimine (PEI) was evaluated for high-density cultivation of immobilized hybridoma c ells. The carrier was used either in suspension or in fixed bed. For s uspended carriers, the effect of carrier pore size, ion-exchange capac ity (IEC), mixing intensity and inoculum concentration on the attachme nt and growth of HBs MAb-producing hybridoma cells in carrier CELLSNOW EX were studied. The carrier with 100 mu m pore size was more efficie nt than that with 500 mu m in supporting cell attachment. In addition, the amount of antibody which was detected by PHA (passive hemagglutin ation assay) was 4-times higher in 100 mu m compared with 500 mu m por e size. At low initial cell concentration, 2.8 X 10(5) ml(-1), the att ached cells did not grow in the first 7 d as indicated by a negligible glucose consumption. However, cell proliferation was observed at high inoculum, 9 x 10(5) ml(-1). Hybridoma cells were expected to attach f aster to EX with high IEC than with low IEC but results showed no sign ificant difference. A different hybridoma cell line producing monoclon al antibody (MAb) against penicillin-G-amidase was successfully cultiv ated in an axial-flow fixed bed containing CELLSNOW carriers. The spec ific glucose uptake rate as an indicator for cell activity was 24-time s higher compared with conventional chemostat cultures. The CELLSNOW c arrier offers many advantages over other carriers.