Epigenetics on transdifferentiation of ES cells toward TS cells

为了阐明mESC在BMP 4诱导的转分化过程中是否通过TSC样和/或EpiSC样状态，我们研究了转分化过程中中间细胞群的性质。免疫组织化学显示，仅在BMP 4处理的培养物中存在TSC样细胞集落。然后，我们在维持TSC的条件下对BMP 4处理的mESC进行传代培养，从而获得细胞系。DNA微阵列分析显示，与mTSC和mESC相比，新细胞系的基因表达谱与EpiSCs更相似。这些结果表明，BMP 4处理的mESC可以通过两个独立的途径转分化为TC。一种是通过mTSC样状态的途径，另一种是通过mEpiSC样状态的途径。

To elucidate if mESCs pass through TSC-like and/or EpiSC-like state during the process of BMP4-induced transdifferentiation, we investigated nature of intermediate cell population in the transdifferentiation process. Immunohistochemistry revealed the presence of TSC-like cell colonies only in the BMP4-treated cultures. We then subcultured BMP4-treated mESCs under the conditions for maintenance of TSCs, and consequently obtained a cell line. DNA microarray analysis revealed that the gene expression profile of then new cell line is more similar to that of EpiSCs compared to mTSCs and mESCs. These results suggest that BMP4-treated mESCs may transdifferentiate to TCs through two independent pathways. One is the pathway through mTSC-like state and the other through mEpiSC-like state.