FIG. 1.

Genomic stability in cultured adipose stromal cells (ASCs). (A) Mitotic chromosomes were harvested from ASC sample 4 at ~10 population doublings (PD) and examined using G-banding techniques. Twenty metaphase chromosome spreads were analyzed and found to be normal (46,XX). (B) Fluorescence in situ hybridization (FISH) analysis of cultured ASCs using centromere probes specific for the X chromosome (red) and chromosome 17 (green). Nuclei are stained with DAPI (blue). In normal (diploid) female cells there are two X chromosomes (red spots) and two chromosome 17s (green spots). A tetraploid cell exhibits whole genome duplication resulting in an approximate doubling of the nuclear volume and detection of double the normal chromosome number. In a tetraploid female cell there are 4 X chromosomes (4 red spots) and 4 chromosome 17s (4 green spots). (C) FISH analysis of ≥200 cells from ASC samples 1 and 2 at the indicated PD times revealed a high diploid content. Chromosomally aberrant cells (classed as tetraploid or aneuploid) were also detectable at a frequency up to 1.5% (see details in Supplementary Table S1). Split-scale Y axes were used as indicated for better illustration.