For the first two animals (Nos. 1 and 4), we established iPSCs from fibroblasts derived from the oral mucosa using retroviral vectors (Okita et al., 2011). For the other two animals (Nos. 6 and 8), we used peripheral blood mononuclear cells (PBMCs) with nonintegrating episomal vectors (Okita et al., 2013). We selected the best clone from each animal according to the following criteria: a stable embryonic stem cell (ESC)-like morphology of the colonies after passaging, expression of pluripotent markers, few or no integrated transgenes (Figures 1A–1F; Figure S1 available online), and the potential for stable neural differentiation. A PCR analysis revealed that all of the clones with retroviral vectors showed apparent expression of remaining transgenes (Figures S1C and S1D), whereas the clones with episomal vectors never did (Figure S1F). To detect the iPSC-derived cells in a brain, we introduced GFP (Figures 1G and 1H). The selected clones of iPSCs had the potential to generate teratomas in the testes of a severe combined immunodeficiency (SCID) mouse within 12 weeks (Figures 1I–1M).
animals
two
animals
two
testes of a severe combined immunodeficiency (SCID) mouse
generate teratomas
within 12 weeks
weeks