Fig. 3

Tetraploidy is characteristic of an endogenous c-kit+ CIC subpopulation. FVB mouse myocardial, intestine, and bone marrow tissue sections assessed by in situ quantitation of ploidy level at 90 days post birth (scalebar = 20 μm) (a). Compiled quantification of in situ DNA content measured by DAPI fluorescent intensity of the nucleus within 3D reconstruction of tissue demonstrates that cardiac ckit+ CICs have higher ploidy levels compared with ckit+ from intestine or bone marrow (b). Percent of ckit+ cells nuclei with diploid tetraploid and higher ploidy content from myocardial, intestine, and bone marrow tissue (c). Ckit+ cells isolated and cultured from cardiac tissue demonstrate higher ploidy levels compared with cultured ckit+ cells from bone marrow (d), measured by DAPI fluorescent intensity of the nucleus within 3D reconstruction of tissue (scalebar = 150 μm) (e) and propidium iodine fluorescent intensity of the nucleus using flow cytometry (f). G-band karyotype analysis verifies diploid content of cultured ckit+ bone marrow stem cells (g) and bone marrow-derived mesenchymal stem cells (h). **P < 0.01; ***P < 0.001. Data are presented as mean±SEM and analyzed using a t test (d) or one-way ANOVA with Bonferroni post hoc test (b)