Fig. 7
Reduction of DNA content in Lin– c-kit+ CICs following myocardial infarction. Quantitation of in situ nuclear DNA content in adult FVB mice following myocardial infarction measured by DAPI fluorescent intensity of tryptase–, ckit+ CIC nuclei. 3D reconstruction of cardiac tissue was performed at 4, 7, 14, and 21 days post injury in the infarction zone. Normal, age, gender, and strain-matched hearts were used as a control. Tryptase+, a marker of mast cells, was only found in injured hearts within the first week after injury and was not included in the analysis, as shown with tryptase–, ckit+, and tryptase+ ckit+ CICs in the infarction zone of an adult, 7-day post-MI FVB heart (a, scalebar = 150 μm) with a boxed region of higher magnification (b, scalebar = 25 μm). The white arrow identifies cCICs included in the analysis and the orange arrow identifies a mast cell, not included in the study. Compiled dot plot of in situ DNA content per nucleus of lin–ckit+ cells demonstrates higher frequency of diploid levels in the infarction region at all time points post MI (c), and is verified upon quantification of percent diploid, tetraploid, and greater than tetraploid content (d). **P < 0.01; ***P < 0.001. Data are presented as mean ± SEM and analyzed using one-way ANOVA with Bonferroni post hoc test (c)
