Stk 3

To verify the multipotency of UC-MSCs, the cells were induced to differentiate into the adipogenic, osteogenic, and chondrogenic lineages. Adipogenic differentiation was induced in STEMPRO adipogenesis differentiation medium (Invitrogen) for 2-3 weeks and stained, and the differentiation was investigated by staining lipid vesicles with Oil Red O (Sigma). Osteogenic differentiation was induced in STEMPRO osteogenesis differentiation medium (Invitrogen) or STK-3 (DS Pharma Biomedical, Osaka, Japan) for 1-2 weeks, and the differentiation was examined by staining with Arizarin Red S (Sigma) reacting to calcium cation. Chondrogenic differentiation was induced by forming cell aggregates in micromass culture in STEMPRO chondorogenesis differentiation medium (Invitrogen) for 1 week, and the differentiation was assessed by staining anionic glycoconjugates with Toluidine Blue (Sigma). Cell images were acquired using a BZ-X700 microscope (Keyence, Osaka, Japan).

For adipogenic differentiation, the cells were cultured in STEMPRO Adipogenesis Differentiation Medium (Invitrogen) for 2–3 weeks and stained with Oil Red O (Sigma). For osteogenic differentiation, the cells were cultured in STEMPRO Osteogenesis Differentiation Medium (Invitrogen) or STK-3 (DS Pharma Biomedical, Osaka, Japan) for 1–2 weeks and stained with Alizarin Red S (Sigma). For chondrogenic differentiation, micromass of the cells were generated, cultured in STEMPRO Chondorogenesis Differentiation Medium (Invitrogen) for 5–7 days, and stained with Toluidine Blue (Sigma). Cell images were acquired using a BZ-X700 microscope (Keyence, Osaka, Japan).