Figure 4
From: Genomic instability of human embryonic stem cell lines using different passaging culture methods
Germ cell layers components within teratomas. Differentiation of H1 and H9 (picked at different passages and dissociated by manual or enzymatic protocols) into ectoderm, endoderm and mesoderm was quantified using whole section Hematoxylin and eosin stains (A). All lines showed structures representing the 3 lineages (ectoderm, endoderm and mesoderm) and were scored as follows: “ - ” indicating the absence of the tissue; “ + ” and “ ++ ” indicating the existence of differentiated tissues that were respectively moderately (one to 5 focus) or highly (>5 focus) represented. Characteristics of hESC-derived teratomas (B): a, b, c; Hematoxylin and eosin staining of teratoma derived from H1 (passage 63 and treated with enzymatic dissociation). d; Cytokeratin AE1/AE3 immunostaining of teratoma derived from H1 showing epithelial structures. e; Hematoxylin and eosin staining of teratoma derived from H9 (passage 40 and treated with enzymatic dissociation). N, neural tissue (ectoderm); C, cartilage (mesoderm); Ep, keratin-containing epidermal tissue (ectoderm); M, striated muscle (mesoderm); B, bone (mesoderm); E, gut epithelial tissue (endoderm).