Hybridoma Culture in Iron-Rich Protein-Free Medium: Cell Growth, Apoptosis, and Nature of Macromolecules Recovered From the Culture Fluid

Abstract

The iron-rich protein-free supplement stimulated growth of mouse hybridomas under a variety of culture conditions, including batch and perfused bioreactor cultures. Fortification of the basal medium by balanced mixtures of amino acids and vitamins showed a strong positive effect on cell viability and antibody production. Monoclonal antibody preparation of highest purity could be obtained by chromatography on Sepharose S-300 followed by ion-exchange chromatography on Q Sepharose. In addition to monoclonal antibody free nucleosomes were isolated from the culture fluid. The suggestion that the presence of free nucleosomes was a consequence of an apoptotic process in the hybridoma cells was supported by findings of apoptotic particles in the culture fluid and of fragmented DNA molecules in cells harvested in late stationary phase.