Hybridoma cells in a protein-free medium within a composite gel perfusion bioreactor.

A composite gel system has been developed combining the chemical and physical properties of calcium alginate and agarose gels. The results of growing composite gel immobilized hybridoma SPO1 cells in a protein-free medium within a fluidized-bed perfusion bioreactor are presented in this paper. During the continuous operation of this system, the total cell density reached 3.9 x 10(7) cells per ml of beads (viability 79.6%). The specific productivity of monoclonal antibody of the immobilized hybridoma cells reached more than 1.5 micrograms per 10(6) viable cells per hour, compared with 0.5 for non-immobilized viable cells grown in a one liter agitated bioreactor with the same medium. Significant increases in cell metabolic activities, including substrate utilization and byproduct formation, were also observed. Leaching of materials from the beads was evident and the major fraction of released materials was alginate.