Christopherson et al. first showed that DPP-4 inhibition increased stem cell homing to bone marrow (Christopherson et al., 2004), following which Zaruba et al. combined DPP-4 inhibition using Diprotin A with G-CSF-mediated stem cell mobilisation in a murine model of myocardial infarction (Zaruba et al., 2009). This evidence concerns the gene DPP4 and myocardial infarction.