The effects of selenium and manganese on growth of hybridomas in serum-free medium were studied. The optimum growth-supporting concentration of Na2SeO3 was about 50 nM. Omission of selenite resulted in decreased growth (60-70% of the number of cells growing with selenite when cultivated for 3 days). The optimum growth-supporting concentration of MnCl2 was 0.5 nM. The number of hybridoma cells growing 3 days without MnCl2 represented about 80% of the cell number obtained by cultivation with MnCl2. Compounds of other trace elements did not display growth-stimulating activity, when tested in short-term culture, perhaps with the exception of lithium at relatively very high concentrations (about 0.2-0.6 mM).

Institute of Molecular Genetics Czechoslovak Academy of Sciences Praha