Cardiomyocyte transplantation reduces the percentage of CCR2+ monocyte-derived macrophages along with Treg cells during the acute MI response in the heart as observed using flow cytometry (Figure 2) while also having long term effects on the prevalence of macrophages as evidenced by the increased CD68 numbers in the remote area of the heart four weeks after MI (Figure 3H). The gene discussed is CCR2; the disease is myocardial infarction.