Neutrophils are the most abundant type of leukocyte in your body. They are produced in your bone marrow, where most live out their relatively short life. However, some do make it out into your bloodstream. Those in circulation are mobile and readily available to participate in an immune system response.
Neutrophils are quickly drawn to a site of a pathogen invasion by inflammation. Once there, these white blood cells have the capability of launching a mixture of defense mechanisms, particularly against bacteria and fungi. Because of all that they do, this aspect of your immune system response may best be described as infection containment. The following explains why.
A neutrophil releases cytokines, which increases inflammatory reactions by other cell types. Inflammation causes vasodilation, which allows for larger immune cells (e.g. macrophages) to migrate into the location and assist in annihilating the threat. The sooner a health threat is neutralized, the less it has an opportunity to spread. Thus, containment achieved with less collateral damage.
Neutrophils are categorized as granulocytes and phagocytes. This means they can release tiny sacs of enzymes into an area that may kill on contact. Or they can engulf and break apart the offending microorganism. Both of these strategies can slow multiplication and spreading of an infection until reinforcements arrive.
Finally, neutrophils have the ability to form a network of fibers that bind or entrap pathogens, known as NETs. The fiber matrix helps hold the invading cells in place, concentrates destructive granules around invaders and minimizes damage to adjacent host cells because granules are less spread out.
Low neutrophil count is called neutropenia. The reduced numbers weakens your initial barrier to bacteria and fungal, thus causing the health effect of a higher susceptibility to infections. Reasons why your neutrophil count may be low are a genetic disorder, viral infection, chemotherapy, radiation treatment, aplastic anemia, leukemia and certain vitamin deficiencies.
High neutrophil count is a very common finding during your body’s process of fighting a bacterial infection. Other causes for an increased count are inflammation, allergens, chronic myeloid leukemia, prednisone and appendicitis.
Measuring the amount of neutrophils is often a component of diagnostic blood count tests.