PEG-rhuMGDF–dependent ES cell–derived hematopoietic progenitors.

mpl^−/−, mpl^−/− flmpl, mpl^−/−Δ3mpl, or mpl^−/− Δ34mpl EBs6 were dissociated and replated for progenitor assay in the presence of PEG-rhuMGDF. Values represent the mean of duplicate dishes in 3 independent experiments.