RESUMEN
<p><b>OBJECTIVE</b>To explore cell culture techniques for amplification of oval cells with preservation simultaneously of the stem cell characteristics.</p><p><b>METHODS</b>Oval cell line OC3 was cultured in RPMI 1640 supplemented with 15% fetal bovine serum and 20 µg/L EGF. Cells were harvested every 5 passages and were examined with biomarkers including OV-6, c-kit, gamma-glutamyl transpeptidase, placental form of glutathione-S-transferase (GST-P), pyruvate kinase M₂, pyruvate kinase L and albumin using techniques including RT-PCR, immunocytochemistry, and enzymo-cytochemistry.</p><p><b>RESULTS</b>OC3 cell lines could be amplified abundantly in-vitro associating with expression of infant liver cell markers at various level, including OV-6, c-kit, gamma-glutamyl transpeptidase, GST-P, pyruvate kinase M₂, but no expression of mature hepatocyte markers detected including pyruvate kinase L and albumin.</p><p><b>CONCLUSIONS</b>Amplification of OC3 cells with preservation of the stem cell phenotype and high proliferation index can be achieved up to the 79(th) passages by culturing in RPMI 1640 supplemented with 15% fetal bovine serum and 20 µg/L EGF.</p>