Characteristics
Neutrophil granulocytes have an average diameter of 12–15 micrometers (µm) in peripheral blood smears. When analyzing a pure neutrophil suspension on an automated cell counter, neutrophils have an average diameter of 8–9 µm.
With the eosinophil and the basophil, they form the class of polymorphonuclear cells, named for the nucleus's multilobulated shape (as compared to lymphocytes and monocytes, the other types of white cells). The nucleus has a characteristic lobed appearance, the separate lobes connected by chromatin. The nucleolus disappears as the neutrophil matures, which is something that happens in only a few other types of nucleated cells. In the cytoplasm, the Golgi apparatus is small, mitochondria and ribosomes are sparse, and the rough endoplasmic reticulum is absent. The cytoplasm also contains about 200 granules, of which a third are azurophilic.
A minor difference is found between the neutrophils from a male subject and a female subject. The cell nucleus of a neutrophil from a female subject shows a small additional X chromosome structure, known as a "neutrophil drumstick".
Neutrophils will show hypersegmentation (many segments of nucleus) in B12 and folate deficiency.
Neutrophils are the most abundant white blood cells in humans (approximately 1011 are produced daily); they account for approximately 50-70% of all white blood cells (leukocytes). The stated normal range for human blood counts varies between laboratories, but a neutrophil count of 2.5–7.5 x 109/L is a standard normal range. People of African and Middle Eastern descent may have lower counts, which are still normal. A report may divide neutrophils into segmented neutrophils and bands.
When circulating in the bloodstream and unactivated, neutrophils are spherical. Once activated, they change shape and become more amorphous or amoeba-like and can extend pseudopods as they hunt for antigens.
Read more about this topic: Neutrophil Granulocyte