Click on image to view larger version.

Figure 1 In Vivo Transplantation of Undifferentiated hESC Results in Teratoma-Like Structures

(A) Hematoxilin and eosin staining of a teratoma within the infarcted area. Note the presence of early stage hyaline cartilage (right, top) and gastrointestinal-like columnar epithelium (right, bottom). (bars: left 500 µm, middle 200 µm, right 100 µm). (B) Immunostaining for the pluripotent markers Tra-1-60 (top) and Tra-1-81 (bottom). Note the positive staining of undifferentiated human embryonic stem cell (hESC) colonies (left) and the absence of staining in cells isolated from the contracting embryoid bodies (EBs) (right) (bar: 100 µm). (C) Troponin I immunostaining of cells isolated from the contracting EBs (bar: 60 µm).