Characterization of iPS cells with abnormal karyotype. A) Control iPSC-K3 cells were generated from human foreskin fibroblasts and have a normal diploid male (46, XY) karyotype. B) A sub-line of iPSC-K3 cells, referred to as iPSC-K3aneuploid, have an abnormal near-tetraploid karyotype as well as rearrangements in chromosome 17 (red arrow). The karyogram presented here is representative of the cells analyzed. C) Left panel shows a phase contrast micrograph of iPSC-K3aneuploid cells in culture. Immunocytochemistry revealed the presence of OCT4 (middle panel) and DAPI was used to identify cell nuclei. Scale bar = 100 μm. D) FACS analysis reveals that iPSC-K3aneuploid cells do not express a marker of differentiated cells, CD13 (left panel); however, pluripotent markers SSEA-4 (middle panel) and Tra-1-81 (right panel) are expressed on the surface of 99% and 96% of the cells, respectively. Isotype controls for each antibody are indicated by the red line, antibodies by the blue line.