The suitable feeder cell layer is important for culture of embryonic stem (ES) cells. In this study, we
investigated the effect of two kinds of the feeder cell, MEF cells and STO cells, layer to mouse ES (mES) cell culture for
maintenance of stemness. We compare the colony formations, alkaline phosphatase (AP) activities, expression of pluripotency
marker genes and proteins of D3 cell colonies cultured on MEF feeder cell layer (D3/MEF) or STO cell layers (D3/STO)
compared to feeder free condition (D3/–) as a control group. Although there were no differences to colony formations and AP
activities, interestingly, the transcripts level of pluripotency marker genes, Pou5f1 and Nanog were highly expressed in D3/MEF (79 and 93) than D3/STO (61and 77) or D3/– (65 and 81). Also, pluripotency marker proteins, NANOG and SOX-2, were more synthesized in D3/MEF (72.8±7.69 and 81.2±3.56) than D3/STO (32.0±4.30 and 56.0±4.90) or D3/– (55.0±4.64 and 62.0±6.20). These results suggest that MEF feeder cell layer is more suitable to mES cell culture. Key words : Mouse embryonic stem cell, Feeder cell, Pluripotency marker, MEF feeder cell

• Yun-Gwi Park(Stem Cell Research Center, Jeju National University, Faculty of Biotechnology, College of Applied Life Sciences, Jeju National University)
• Seung-Eun Lee(Stem Cell Research Center, Jeju National University, Faculty of Biotechnology, College of Applied Life Sciences, Jeju National University)
• Eun-Young Kim(Stem Cell Research Center, Jeju National University, Faculty of Biotechnology, College of Applied Life Sciences, Jeju National University, Mirae Cell Bio)
• Hyuk Hyun(Stem Cell Research Center, Jeju National University, Faculty of Biotechnology, College of Applied Life Sciences, Jeju National University)
• Min-Young Shin(Stem Cell Research Center, Jeju National University, Faculty of Biotechnology, College of Applied Life Sciences, Jeju National University)
• Yeo-Jin Son(Stem Cell Research Center, Jeju National University, Faculty of Biotechnology, College of Applied Life Sciences, Jeju National University)
• Su-Young Kim(Dept. of Preventive Medicine, College of Medicine, Jeju National University) Corresponding Author
• Se-Pill Park(Stem Cell Research Center, Jeju National University, Faculty of Biotechnology, College of Applied Life Sciences, Jeju National University, Mirae Cell Bio) Corresponding Author