Growth of human x human hybridomas in protein-free medium supplemented with ethanolamine

A protein-free medium was developed which supports the growth of human X human hybridomas derived from the fusion partner KR-4. This medium consists of a 1:1 mixture of Iscove's modified Dulbecco's medium and Ham's F-12 medium supplemented with 300 microM ethanolamine. The addition of ethanolamine was essential to maintain cell viability and proliferation. Phosphoethanolamine could not substitute for ethanolamine. Although the maximal cell density achieved in protein-free medium was lower than that in medium supplemented with albumin and transferrin, immunoglobulin production was still supported. This protein-free medium may be useful for large-scale cultivation and for metabolic and immunologic studies of human hybridomas.