The Effect of Murine Leukemia Inhibitory Factor on In Vitro Differentiation of Mouse Embryonic Stem Cells

Embryonic stem cells (ESc) are pluripotent cells which have been used as a model tostudy the mechanism that control the embryogenesis and early mammalian development in vitro.The aim of this study was to isolate and produce embryonic stem cells from late blastocyst stageembryos in mice.

Blastocyst stage embryos from pregnant NMRI mice were obtained andcultured for 24 h in DMEM medium. 4-6 days after hatching, the inner cell masses (ICM) formedcolonies which were then collected mechanically and trypsinized. Several subcultures were preparedin the medium supplemented with 0.1 mM 2 Mercaptoethanol, 1000 U/ml Leukemia InhibitoryFactor (LIF) and 10% Fetal Bovine Serum (FBS). The (ESc) were recognized by alkaline phosphateshistochemistry using azo-coupling method.

The results demonstrated that a highly pluripotent stem cell line was derived from theblastocyst stage embryos of NMRI mice; however, the rate of colonies was as low as 10%.

The LIF is effective to culture and maintain the isolated ICM colonies inundifferentiated condition in the absence of feeder layer.