As neutrophils use degranulation of proteolytic enzymes to combat infections (30–33), we examined the presence of granule-related proteins for azurophilic (neutrophil elastase) and specific (lactoferrin) granules within the different BM neutrophil precursors by confocal imaging, and confirmed that they are indeed contained within their cytoplasm in steady state (Suppl. Here, ELANE is linked to infection.