Microarray Expression Data from Haematopoietic Differentiated Human Embryonic Stem Cells

The underlying mechanisms which are responsible and govern early haematopoietic differentiation during development are poorly understood. Gene expression comparison between pluripotent human embryonic stem cells and earliest haematopoietic progenitors may reveal novel transcripts and pathways and provide crucial insight into early haematopoietic lineage specification and development. Understanding of transcriptional cues that direct differentiation of human embryonic stem cells (hESC) to defined and functional cell types is essential for their future clinical applications. In this study we have undertaken a comparative transcriptional approach of haematopoietic progenitors derived from hESC at various stages of a feeder and serum free differentiation method and have shown that the largest transcriptional changes occur during the first four days of differentiation. Data mining based on molecular function pointed to RhoGTPase signalling as key regulator of this differentiation. Inhibition of this pathway using a chemical inhibitor (Y26732) resulted in a significant downregulation of haematopoietic progenitors throughout the differentiation window, thus uncovering a previously unappreciated role for RhoGTPase signalling in differentiation of hESC to haematopoietic lineages. There are a total of 4 samples within this microarray experiment with 2 biological replicates for each sample. Pluripotent human embryonic stem cells (day 0) underwent haematopoietic differentiation and at various stages of development (day 4, day 6, day8) differentiated cells were FACS sorted for two key haemangioblast markers, CD31 and KDR.