Similar regulation of nuclear Klf4 expression was observed in human heart samples after myocardial infarction (Figure 5B) with a mean percentage of Klf4 positive cells (±SD) of 72%±10.0% in the BZ and 7%±4.5% in the IZ (P-value < 0.001). This evidence concerns the gene KLF4 and myocardial infarction.