azurophilic granule azurophilic granule an azurophilic granule is a cellular object readily stainable with a romanowsky stain. in white blood cells and hyperchromatin, staining imparts a burgundy or merlot coloration. neutrophils in particular are known for containing azurophils loaded with a wide variety of anti-microbial defensins that fuse with phagocytic vacuoles. azurophils may contain myeloperoxidase, phospholipase a2, acid hydrolases, elastase, defensins, neutral serine proteases, bactericidal/permeability-increasing protein, lysozyme, cathepsin g, proteinase 3, and proteoglycans. azurophilic granuledetailsidentifierslatingranulum azurophilumthh2.00.04.1.02011, h2.00.04.1.02014 anatomical terms of microanatomy azurophil granules are also known as "primary granules". furthermore, the term "azurophils" may refer to a unique type of cells, identified only in reptiles. these cells are similar in size to so-called heterophils with abundant cytoplasm that is finely to coarsely granular and may sometimes contain vacuoles. granules may impart a purplish hue to the cytoplasm, particularly to the outer region. occasionally, azurophils are observed with vacuolated cytoplasm.