Dialysis cultures with immobilized hybridoma cells for effective production of monoclonal antibodies

Abstract

An industrial scale reactor concept for continuous cultivation of immobilized animal cells (e.g. hybridoma cells) in a radial-flow fixed bed is presented, where low molecular weight metabolites are removed via dialysis membrane and high molecular products (e.g. monoclonal antibodies) are enriched. In a new “nutrient-split” feeding strategy concentrated medium is fed directly to the fixed bed unit, whereas a buffer solution is used as dialysis fluid. This feeding strategy was investigated in a laboratory scale reactor with hybridoma cells for production of monoclonal antibodies. A steady state monoclonal antibody concentration of 478 mg l^-1 was reached, appr. 15 times more compared to the concentration reached in chemostat cultures with suspended cells. Glucose and glutamine were used up to 98%. The experiments were described successfully with a kinetic model for immobilized growing cells. Conclusions were drawn for scale-up and design of the large scale system.

Abbreviations: c_Glc – glucose concentration, mmol l^-1; c_Gln – glutamine concentration, mmol l^-1; c_Amm – ammonia concentration, mmol l^-1; c_Lac – lactate concentration, mmol l^-1; c_MAb – MAb concentration, mg l^-1; D – dilution rate, d^-1; D_i – dilution rate in the inner chamber of the membrane dialysis reactor, d^-1; D₀ – dilution rate in the outer chamber of the membrane dialysis reactor, d^-1; q*_FB,Glc – volume specific glucose uptake rate related to the fixed bed volume, mmol l_FB ^-1 h^-1; q*_FB,Gln – volume specific glutamine uptake rate related to the fixed bed volume, mmol l_FB ^-1 h^-1.