Neutrophil: Background of the Study
Neutrophil is a variety of granulocyte (a type of white blood cell) distinguished by a dense nucleus consisting of between two and five lobes, and a pale cytoplasm with irregular outline containing many fine pink-blue (azurophilic) or grey-blue granules (Hoffbrand, 2006).
Neutrophils form an essential part of the innate immune system which means that they can “non-specifically” destroy any invaders that they encounter in the body such as bacteria and parasites (non-specifically means that neutrophils do not have to recognize the invaders specifically, but simply identify them as something that should not be present in the body and should be destroyed (Suzanne, 2009).
In general they are referred to as either neutrophil granulocytes or polymorphonuclear neutrophil (PMNs), they form part of the polymorphonuclear cell family together with basophils and eosinophils (Witko et al., 2002, Klebanoff et al., 1978, and Nathan, 2006). Neutrophils undergo a process called chemotaxis which allows them to migrate towards sites of infections. Jitesh proposed that neutrophils are the first to increase in case of infection (Dana, 2011), also the first responders to invasion, these often takes place within an hour.
Absolute neutrophil count (ANC) is a measure of the number of nentrophil granulocyte (Al-Gwaiz et al., 2007) present in the blood. The result of the test are routinely checked during cancer treatment to determine how the immune system is responding to treatment.
The ANC is calculated from measurement of the total number of white blood cells, usually based on combined percentage of matured neutrophils (Segmented cells) and bands (Immature neutrophils).
Individual is considered to be apparently healthy when the person is perceived or understood (according to appearances) to be free from disease or ailment i.e as far as one knows; that he or she is free health wise. Therefore, the normal range of neutrophil for apparently healthy individual is 1.5-8.0 (i.e 1,500-8,000/mm3). A “safe” ANC is 500 – 1500; a low ANC is less than 500. A safe ANC means that the subject’s activities do not need to be restricted (on the basis of the ANC).
Justification of the Study
Neutrophils are recruited to the site of injury within minutes following trauma and are the hallmark of acute inflammation (Cohen et al., 2002), and play a key role in the front-line defence against invading pathogens. Neutrophil have three strategies for attacking microorganisms; phagocytosis (ingestion), release of soluble anti-microbials and generation of neutrophil extracellular traps (NET) (Hickey et al., 2009).
The standard range for absolute neutrophil count 1.5 - 7.5 X 109/l, was calculated based on the values generated from the Caucasian population (Reich et al., 2009), but previous studies done on African and Afro-caribbean groups found lower counts for these population compared with Caucasians.
It has been taken into consideration the fact that, about half the neutrophils in the blood, circulate to form circulating pool (included in WBC count) while the other half marginate along the walls of the blood vessels and capillaries, forming marginated pools (not included in WBC count). Increased number of the neutrophil in the marginated pool may explain the lower circulating neutrophil counts frequently found in Africans (Monica, 2000). This is a phenomenon of which its etiology remains unknown.
Aims and Objectives
• To determine the absolute neutrophil count in healthy individuals.
• To determine if the standard range of absolute neutrophil count should also be recommended for African descent.
Neutrophil: Background of the Study