Bone tissue engineering of induced pluripotent stem cells cultured with macrochanneled polymer scaffold

A reliable source of osteogenic cells is an essential factor for bone tissue engineering. In this study, human-induced pluripotent stem cells (hiPSCs) without an embryoid body step were cultured in macrochanneled poly(caprolactone) (PCL) scaffolds prepared using a robotic dispensing technique, after which osteogenesis was promoted by the addition of exogenous osteogenic factors. The osteogenesis of the hiPSCs was demonstrated based on the detection of osteogenic molecules, such as osteopontin, using flow cytometry analysis, quantitative polymerase chain reaction and western blotting. Thereafter, the cell-scaffold constructs were transplanted into the subcutaneous site of male athymic mice. At 4 weeks after implantation, histological assays (hematoxylin & eosin staining, Alizarin red staining, and osteocalcin immunostaining) were conducted to determine the bone induction of hiPSCs. The results indicated a production of pronounced levels of extracellular matrices and their mineral deposition within the cell-scaffold implant, suggesting possible in vivo bone induction by the hiPSCs-based tissue engineering approach. The results presented here provide useful information regarding the tissue engineering of bone utilizing hiPSCs in conjunction with cell-supporting scaffolds.