본 연구에서는 LIF의 첨가가 분리된 할구 유래의 생쥐 배아줄기세포 확립에 미치는 영향을 살펴보았다. 과배란 유도된 BDF1 생쥐로부터 2-세포기의 배아를 회수하여 각기 LIF가 첨가되지 않은 배양액과 1,000, 2,500, 5,000 U/mL의 LIF가 첨가된 배양액에서 포배기 배아까지 배양하였다. 배양된 포배기 배아는 차별화 염색 방법을 이용하여 내세포괴와 영양외배엽의 수를 계수하였다. 2,500 U/mL의 LIF 첨가 시 대조군( vs. , P<
This study was carried out to investigate the effect of leukemia inhibitory factor (LIF) on the derivation of mouse ES cells from isolated blastomeres. Two-cell stage mouse embryos were obtained from superovulated BDF1 female mice. Collected embryos were cultured to blastocyst stage in culture medium supplemented with 0, 1,000, 2,500 or 5,000 U/mL of LIF. Cultured blastocysts were examined by counting the number of cells in the inner cell mass (ICM) and trophectoderm (TE) using differential staining method. When 2-cell embryos were cultured with 2,500 U/ml of LIF, the cell numbers of ICM significantly increased in comparing with those of the control( vs. , P<0.01) and 1,000 U/mL of LIF-containing group ( vs. , P<0.05). We used an ES cell establishment medium with 20% Knockout Serum Replacement and 0.01 mg/mL ACTH instead of fetal bovine serum. Establishing efficacy of ES cell lines were the highest in 2,500 U/mL of LIF-containing group as 36.7% (11/30). This culture medium was applied to the culture of isolated blastomeres and to derivate ES cell lines. Three ES cell lines (21.4%) from isolated blastomeres of 2-cell stage embryos were established. In further experiments, we could establish one ES cell line (4.0%) from single blastomere of 4-cell stage embryo. The subcultured ES cells and their embryoid bodies were characterized by analyzing gene expression for undifferentiation and differentiation marker gene using immunocytochemistry and RT-PCR. In conclusion, LIF supplementation in culture medium could increase the cell number in ICM of blastocysts and support derivation of ES cell lines from isolated blastomeres.