The use of low-molecular-weight components from adult cattle serum in culture of hybridoma cells in vitro.

Adequate amounts (3.5-14%) of low-molecular weight fractions from adult cattle serum (LMW-CS) passed through an /Amicon PM30 filter (mol. wt. exclusion = 30000), 20 microM ethanolamine (E), 10 mg/l transferrin (T), 10 mg/l insulin (I), and 40 nM sodium selenite (S), used as the substitutes for fetal calf serum (FCS), were added to the basic medium, RPMI1640 or a 1:1 mixture (by volume) of IMDM (Iscove's Modified Dufbecco's Medium) and Ham's F12, to compose the experimental "serum-free" medium. Maximum density of hybridoma cells cultured in such medium can reach and sometimes exceed that in FCS-containing medium. For the growth of hybridoma cells, 4% LMW-CS in the medium was found to be able to meet the basic requirement; ethanolamine was the primary growth-supporting factor among the 4 essential supplements of T, I, E, and S; and a significant synergistic action on the cell growth was found between LMW-CS and TIES.