CD300A and congestive heart failure: Together, these results suggest that CD300a deficiency prevents the development of CHF after MI/R via both SiglecFhi and SiglecFlo neutrophils: CD300a deficiency in tissue-resident macrophages increased efferocytosis and thereby decreased DAMPs, which directly reduced inflammation-associated tissue injury and indirectly reduced it via decreasing the generation of pathogenic SiglecFhi neutrophils.