We recently identified a novel way to promote the self-renewal of mouse embryonic stem (ES) cells: activating the Wnt-beta catenin pathway while blocking the MAP Kinase pathway.
This discovery enables us to develop a fully defined culture system for the maintenance of pure populations of mouse ES cells.
Using this system, we are elucidating differences between mouse ES cells and epiblast stem cells in their requirements for extrinsic stimuli that sustain pluripotency.