Lazar_1988_Cytotech_1_331

A fixed bed perfusion system for hybridoma cell immobilization is presented. The system consists of a culturing vessel (300 ml total volume) in which polyurethane (PU) sponges in the form of small cubes of about 5 mm sides are packed. Cells are immobilized by physical entrapment in the foam matrix. By entrapment of the cells in the pores of the matrix high cell concentration can be maintained in a mechanically protected environment. Medium is continuously circulated by an airlift pump mounted in the cell-free chamber (700 ml total volume).Medium flow rate, feeding rate, dissolved oxygen, pH, nutrient uptake and waste product formation can be easily monitored and controlled. Steady state conditions are established with medium dilution rates of 1.0-1.5 reactor volume per day. The steady state is characterized by a constant cell density, constant culture volume and constant glucose and lactate levels. Cell-free supernatant is collected continuously in a cold room adjacent to the 37 degrees C culture room. Monoclonal antibodies (MAb) are produced at a concentration of 150-200 mug/ml for several weeks. An important feature of the system is the capacity to maintain a population of cells after the growth phase in a non-proliferating state for extended time periods expressing high titers of MAb.