1–6 weeks post MI, macrophages may transition to fibroblast-like cells, capable of secreting collagen (Haider et al., 2019) IL-10 and TGFβ secreting macrophages promote myofibroblasts transdifferentiation (O’Rourke et al., 2019) 1 week post ischemia/reperfusion, loss of MCP-1 is associated with decreased macrophage infiltration and interstitial fibrosis (Frangogiannis et al., 2007) 4 weeks post MI, Gata6 expressing pericardial macrophages limit cardiac fibrosis (Deniset et al., 2019). Here, CCL2 is linked to myocardial infarction.