Figure 4.

Integrating cMYC vector imposes tumorigenic load in iPSCs. (A): Four groups of SCID-beige mice (n = 3) received pancreatic progenitor cells from control, Lenti-GFP-, Lenti-cMYC- and Lenti-OSKM-superinfected TGF-iPSCs through transplantation into renal capsules of recipient SCID-beige mice. Three weeks after transplantation, left kidneys with iPSC grafts were recovered. Representative images of left kidneys with iPSC grafts are shown. Scale bars indicate 1 cm. (B): The averages of total kidney and graft weights were determined and compared among control, Lenti-GFP-, Lenti-cMYC- and Lenti-OSKM groups. *, p < .05 versus control by t test. Data represent the mean ± SEM. (C): Cross-sections of the junctions between the kidney and iPSC-derived grafts were visualized upon H&E staining. The junctions are indicated by a green line. Scale bars = 200 µm. Abbreviations: GFP, green fluorescent protein; iPSCs, induced pluripotent stem cells; OSKM, OCT4, SOX2, KLF4, and cMYC; TGF-iPSCs, transgene-free induced pluripotent stem cells.