Experimental methodology. Bone marrow mononuclear cells (BMMNCs) were isolated from bone marrow aspirates by Lymphoprep, before further enrichment of a subset of samples by magnetic activated cell sorting selection for the STRO‐1 antigen. Samples were then immediately analyzed by flow cytometry or ImageStream, or were subject to either a transient (24 hours; short‐term) or prolonged (14 days; long‐term) stimulation with Wnt3A. After transient stimulation, cells were analyzed by flow cytometry or ImageStream, or following 14 days of adherent culture in basal or osteogenic media, assayed for osteogenic differentiation potential (high density seeding) or CFU‐F and CFU‐O formation efficiency (low density seeding). Cells were also assayed after 14 days of ongoing, prolonged stimulation with Wnt (high density seeding) for their osteogenic differentiation potential. Abbreviations: ALP, alkaline phosphatase; BMMNCs, bone marrow mononuclear cells; BMSC, bone marrow stromal cell; CFU‐F, colony forming unit fibroblast; CFU‐O, colony formation in the presence of osteogenic medium; FACS, fluorescence‐activated cell sorting; MACS, magnetic activated cell sorting; MSCs, mesenchymal stem cells.