A novel human hepatoblastoma cell line (HuH-6KK) with rapid growth in serum-free medium without extracellular matrix.

A novel human hepatoblastoma cell line (HuH-6KK) with a high growth rate in a serum-free medium without extracellular matrix was developed from an original one, HuH-6 c15 (HuH). The original HuH cells (38 passages) did not proliferate well in RPMI 1640 medium containing 20% fetal calf serum (FCS). The HuH cells (HuH-6KK) with a high growth rate were selected by culturing them in an enriched RDF containing 20% FCS and 0.01% mucous polysaccharide (spirulinan) isolated from a blue-green alga, Spirulina subsalsa. The HuH-6KK cells showed a rapid growth in serum-free eRDF medium containing insulin, transferrin, ethanolamine, and selenite (eRDF-ITES medium) without fibronectin. The proliferation of the original HuH cells was also observed in the eRDF-ITES medium, but the growth was slow compared with the HuH-6KK cells. In the medium without ITES, the growth of the HuH-6KK and original HuH cells was slow. Among the ITES ingredients, insulin promoted the growth of HuH-6KK cells the most.