Removing Murine Embryonic Stem Cells from the differentiating cell culture by Using Magnetic Activated Cell Sorting
免疫磁珠分选降低分化体系中胚胎干细胞的比例

The objective of the study is to remove murine embryonic stem cells (mESC) from the differentiating cell culture and purify the differentiated cells by Magnetic Activated Cell Sorting (MACS). Neural differentiation of mESC was induced by a 5-stage method. The specific cell surface marker, SSEA-1, was used to identify ES cells in the differentiating cells. The optimal dilutions of mouse anti mouse SSEA-1 IgM primary antibody and FITC conjugated goat anti mouse secondary antibody were determined before the flow cytometry test. The incubation time and incubation temperature of primary antibody were all optimized to make the cytometry test accurate. After the optimization, stage 4 cells were dissociated into single cell suspension, incubated with antibody of SSEA-1 and microbeads conjugated goat anti mouse IgM, and then sorted through the magnetic field. The rate of SSEA-1 positive cells in pre- and post- separation groups was assessed by flow cytometry, and the viability of cells was evaluated by trypan blue staining counting under light microscopy. The proportion of SSEA-1 positive cells in the separated cells can be reduced from (7.19±1.36) % to (1.34±0.80) %. The survival rate of sorted cells was more than 92%, similar to that of pre-separation cells. The MACS system we used can effectively remove mESC from the differentiated cells. The sorted cells will be well provided for the subsequent studies about transplantation therapy.