The mature neutrophil has a nucleus divided into 3-5 lobes containing heterochromatin at the periphery and euchromatin in the centre. It has a very active cytoplasm tuned to produce and store mediators vital for function. There are two types of cytoplasmic granule.
Neutrophilic specific granules are small and numerous. They contain antibacterial agents lactoferrin and lysozyme and are also positive for the enzyme alkaline phosphatase.
Azurophilic lysosomal granules are less abundant, act as the lysosomes of neutrophils and contain a variety of enzymes:
The cytoplasm of the neutrophil also contains a highly adaptable cytoskeleton. Abundant actin filaments, microtubules and glycogen permit change between an essentially round shape during haematogenous circulation to an amoeboid-like cell during active movement to sites of inflammation.
The surface of the cell is rich in receptors for vascular endothelium, cell matrix molecules, inflammatory mediators and organisms.
Last reviewed 01/2018