Fig. 3

Differentiation potential of Wilms’ tumor factor 1 (WT1)-positive (WT1^pos) cells into cardiac lineages. The WT1^pos cells (WT1-pos) showed small and round morphology (a) and, when induced under defined conditions (3% FCS + 5% horse serum) on gelatin-coated dishes, they became elongated and formed giant cells 12 days after induction (dpi) and developed spontaneously contracting activity in the dish. The morphometric changes were not observed in WT1^neg populations (WT1-neg) under identical culture conditions. Immunocytochemistry further revealed the formation of ramified vessel-like structures with the expression of the endothelial marker von Willebrand factor (vWF) and myogenic lineage expressing cardiac troponin T (cTnT) that formed striation structures (b)