Effect of MTA and EFA on normal bone marrow BFU-Es and CFU-GMs. Bone marrow cells were treated with increasing concentrations of (A) MTA or (B) EFA for 14 days after which (•) BFU-Es and (▴) CFU-GMs were enumerated as described in “Materials and methods.” All assay conditions were performed in triplicate and error bars represent standard deviation.