MEF-CM and UM_GTA re-stimulation experiment with human ES cells

Human embryonic stem cells can be maintained in a basic Serum Replacement (Invitrogen) based medium that has been conditioned on mouse embryonic fibroblasts (MEFs), yielding MEF-CM. Ligands secreted into the medium by the MEFs include Activin A, TGFß1, and Gremlin. This experiment served the purpose of identifying the short-term effects of MEF-CM and its substitute UM_GTA (unconditioned medium plus Activin A, TGFb1, and Gremlin) on gene expression in human embryonic stem cells. Keywords: Media / growth factor stimulation experiment hES cells were grown in MEF-CM, then in unconditioned medium for 1 day. Cells were then re-stimulated with MEF-CM or UM_GTA for 4h to be compared to non-stimulated samples. The experiment was carried out in the presence of 5+5 (MEF-CM) or 10 ng/ml (UM, UM_GTA) of FGF2. Activin A was used at 20 ng/ml, TGFß1 at 2 ng/ml, and Gremlin at 200 ng/ml. Two biological replicates were hybridised per sample type.