Gene microarray of human embryonic stem cells, differentiated at three development stages, to investigate changes in the genomic transcripts associated with their glycome.

We are interested in investigating changes in both the glycome and transcriptome of human embryonic stem cells upon differentiation. We have chosen as a model system to differentiate human ES cells into neural spheres using a published protocol by Zhang, S.C. et al. (2001; Nat Biotech. 19: 1129-33). Based on the information provided by microarray analysis, proteins of interest can be further investigated to associate a particular glycosyltransferase, for example, with production of a specific glycan structure at a particular stage. Techniques such as the use of RNAi for the knock-down or transfection of hESCs to effect the overexpression of the transcript, followed by subsequent analysis of the glycan structures can be employed. Three developmental stages will be investigated: Stage 1: undifferentiated stem cells; Stage 2: differentiation into embryoid bodies; Stage 3: differentiation into neural spheres. In addition to characterizing the cell surface for glycomic “fingerprints” we want to characterize the genomic transcripts associated with the glycome.