An azurophil is an object readily stained with an azure

Lapis lazuli

Lapis lazuli is a relatively rare semi-precious stone that has been prized since antiquity for its intense blue color....

 dye

Dye

A dye is a colored substance that has an affinity to the substrate to which it is being applied. The dye is generally applied in an aqueous solution, and requires a mordant to improve the fastness of the dye on the fiber....

. Azurophils include certain cytoplasmic granules

Granule (cell biology)

In cell biology, a granule is a small particle. It can be any structure barely visible by light microscopy. The term is most often used to describe a secretory vesicle.-Leukocytes:...

 in white blood cells and hyperchromatin

Chromatin

Chromatin is the combination of DNA and proteins that make up the contents of the nucleus of a cell. The primary functions of chromatin are; to package DNA into a smaller volume to fit in the cell, to strengthen the DNA to allow mitosis and meiosis and prevent DNA damage, and to control gene...

, imparting a burgundy

Burgundy (color)

Burgundy is a shade of purplish red associated with the Burgundy wine of the same name, which in turn is named after the Burgundy region of France. The color burgundy is similar to other shades of dark red such as maroon...

 or merlot

Merlot

Merlot is a darkly blue-coloured wine grape, that is used as both a blending grape and for varietal wines. The name Merlot is thought to derive from the Old French word for young blackbird, merlot, a diminutive of merle, the blackbird , probably from the color of the grape. Merlot-based wines...

 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

Myeloperoxidase

Myeloperoxidase is a peroxidase enzyme that in humans is encoded by the MPO gene. Myeloperoxidase is most abundantly expressed in neutrophil granulocytes . It is a lysosomal protein stored in azurophilic granules of the neutrophil...

, phospholipase A2

Phospholipase A2

Phospholipases A2 are enzymes that release fatty acids from the second carbon group of glycerol. This particular phospholipase specifically recognizes the sn-2 acyl bond of phospholipids and catalytically hydrolyzes the bond releasing arachidonic acid and lysophospholipids...

, Acid Hydrolases, Elastase

Elastase

In molecular biology, elastase is an enzyme from the class of proteases that break down proteins.- Forms and classification:There exist eight human genes for elastase:Bacterial forms: Organisms such as P...

, defensin

Defensin

Defensins are small cysteine-rich cationic proteins found in both vertebrates and invertebrates. They have also been reported in plants. They are, and function as, host defense peptides. They are active against bacteria, fungi and many enveloped and nonenveloped viruses. They consist of 18-45 amino...

s, neutral serine protease

Serine protease

Serine proteases are enzymes that cleave peptide bonds in proteins, in which serine serves as the nucleophilic amino acid at the active site.They are found ubiquitously in both eukaryotes and prokaryotes...

s, bactericidal/permeability increasing protein

Bactericidal/permeability increasing protein

Bactericidal/permeability increasing protein is a 456 residue protein which is part of the innate immune system.-Distribution and function:...

, lysozyme

Lysozyme

Lysozyme, also known as muramidase or N-acetylmuramide glycanhydrolase, are glycoside hydrolases, enzymes that damage bacterial cell walls by catalyzing hydrolysis of 1,4-beta-linkages between N-acetylmuramic acid and N-acetyl-D-glucosamine residues in a peptidoglycan and between...

, cathepsin G, proteinase 3, and proteoglycans.

Azurophil granules are also known as "primary granules".

External links

• Histology at ucsf.edu