COL1A2 and myocardial infarction: In fibroblast-specific knockout mice (Col1a2-CreERT2+/− CXCR7flox/flox; FKO mice), there was no significant reduction in Cxcr7 expression in the whole heart (Supplementary Fig. S3a,b) and no difference in heart weight, left ventricular volume, and systolic function as compared with Ctl mice, even after myocardial infarction (Supplementary Fig. S3c,d).