To determine which cell type expressing CD300a is involved in cardiac function after MI/R, we used Cd300afl/flLyz2-Cre mice and Cd300afl/flItgax-Cre mice, in which CD300a expression is lacking on phagocytes, including neutrophils and both monocyte-derived and tissue-resident macrophages, and dendritic cells, respectively, in the heart. This evidence concerns the gene CD300A and myocardial infarction.