Tissue after 12 weeks. An increased expansion of fat cells (*) covering up to 60% of the scaffold surface and vessels (thin arrows) was found in all groups after 12 weeks in vivo implantation. Next to the fatty tissue, necrotic areas (°) were detectable in all groups. Pictures on the right side show the inserts in the left pictures. [Gp = Group, os-hMSCs = osteogenically stimulated hMSCs] Toluidine blue: scale bars: 200 μms (left), 50 μms (right).