Additionally, intramyocardial injection of FACS-sorted S100a9+Ly6c+ C6 IMos into P5 hearts after MI resulted in decreased cardiac reparative capacity (Supplemental Figure 7), confirming the detrimental role of S100a9+Ly6c+ C6 cells in cardiac repair after injury. This evidence concerns the gene S100A9 and myocardial infarction.