Optimization of culture parameters and scale-up

The optimization of culture parameters and the scale-up of a human hetero-hybridoma in a stirred bioreactor are described in this section. From the viewpoint of scale-up and handling, a stirred bioreactor is chosen as the most practical approach for industrial-scale production of monoclonal antibodies (MAbs). Furthermore, stirred bioreactors are very flexible with regard to the optimization of culture parameters, i.e. oxygen supply (bubble free, air sparging) and culture mode (e.g. batch, fed-batch, chemostat and perfusion). They also give easy access to cell samples at any time of culture, and keep cells homogeneously supplied with nutrients and oxygen. 

The optimization of culture parameters is an important step in scale-up. The growth rate, the viability and the antibody production of hybridoma cells largely depend on culture conditions. Optimization studies were carried out in a 1.5-1 bioreactor, equipped with pH and pO regulators, that provides reproducible culture conditions and minimizes medium requirements. The results were then applied to a 12-1 bioreactor. 

The heterohybridoma (human x human x mouse) 4-8KH15, used for scale-up, secretes human monoclonal IgM specific for Pseudomonas aeruginosa lipopolysac-charide of Habs serotype 4. The generation and characterization of human hybridomas is described by Lang et al (1989, 1990a). 

Cell and Tissue Culture Laboratory Procedures in Biotechnology, edited by A. Doyle and J.B. Griffiths. 1998 John Wiley Sons Ltd. 

Spinner flasks (Bellco) of 500 ml volume are placed in an incubator aerated with air enriched with 5% CO2. Agitation speed was set at 100 or 150 rpm. 

---