Human Hepatocyte-Derived Induced Pluripotent Stem Cells: MYC Expression, Similarities to Human Germ Cell Tumors, and Safety Issues

Figure 5

iPSC generated from human fibroblasts. The tumors generated were mainly cystic (a, H&E 20x), and derivatives from all three germ cell layers were seen. Intestinal type structures were lined by a mucin producing epithelium, overlying a well-differentiated wall with a smooth muscle layer (b, H&E 100x). Mesodermal derivatives also consisted of immature bone (osteoid) (arrowhead) and cartilage (star), as well as striated muscle (arrow) (c, H&E 100x). Ectodermal derivatives corresponded mainly to immature neuroglial tissue and neuroectodermal rosettes (arrows) (d, H&E 200x).

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