Study Of Isolation, Culture And Identification About Mouse Embryonic Setm Cells

The blastocysts of 3.5d from ICR strain mice were collected, cultured on the fibroblast cell feeder layers that were from the blastocysts of 13.5d from ICR strain mice.The embryonic stem cell colonies were identified, the results can be shown: â‘  They all have typical morphological characteristics of ES cells, such as the nuclear big, cytoplasm little, high ratio of the nuclear-cytoplasm, the obvious nucleoli, the cells compacted to from colonies, the colonies having strong third dimension, round or elliptic, with smooth edges, with strong refraction, and having no clear boundaries of cells within a colony. â‘¡ Positive AKP staining is the typical characteristics of murine undifferentiated ES cells. We checked the activity of AKP of the ES cells using the undifferentiated F0 ES cells from the 3.5d blastocysts which were widely used all over the world as the positive control, and the embryonic fibroblast cells as the negative control. After the AKP staining, all of the ES cells showed strong AKP activity the same as the F0 ES cells.On the contrary, the embryonic fibroblast cells have no expression of AKP showing the lost of staining. â‘¢ One of the criterions for checking the ES cell lines established is the karyotype bearing. A good ES cell line should have at least more 75% cells bearing normal diploid karyotype after 5~10 passages. According to above requirement, there is the ES cells from ICR strain mice with more than 75% normal karyotype. â‘£ F2 ES cells would differentiated to other cells in the MEF layer without mLIF. In the MEF layer and with mLIF,when the ES cells were cultured to F8 or F11 they would differentiated to other cells too.