CD300A and myocardial infarction: Furthermore, compared with WT mice, control mAb injection increased LVFS and LVEF at day 7 and decreased scar area at 4 weeks after MI/R in Cd300a−/− mice, but administration of anti-Ly6G mAb abolished these differences between Cd300a−/− and WT mice (Figure 4, C and D), suggesting that CD300a on neutrophils is involved in angiogenesis, the development of fibrosis, and cardiac function after MI/R.