By flow cytometry analysis of various T-cell lineages in the heart-draining mediastinal lymph nodes (MLNs) at 72 h after MI, we found that the ratios of T helper cells (CD4+CD8-), cytotoxic T cells (CD8+CD4-), and regulatory T cells (Tregs, CD4+CD25+FOXP3+), a T-cell subset that improves cardiac repair post-MI43, were comparable between WT and Dusp6-deficient hearts (Supplementary Fig. 19a–d). Here, CD4 is linked to myocardial infarction.