Neutrophils are a type of white blood cell (leukocyte) that plays a crucial role in the immune system’s response to infection and inflammation. They are one of the first responders to sites of infection or tissue injury. Neutrophils are produced in the bone marrow and make up a significant portion of the body’s total white blood cell count, usually comprising about 50-70% of circulating leukocytes.
These cells are known for their ability to engulf and destroy pathogens such as bacteria, fungi, and other foreign invaders through a process called phagocytosis. Neutrophils contain granules filled with potent antimicrobial substances, including enzymes and reactive oxygen species, which they release to kill pathogens.
In addition to their role in fighting infections, neutrophils also play a role in modulating inflammation and promoting tissue repair. However, dysregulation of neutrophil function can contribute to various inflammatory disorders and autoimmune diseases.
Neutrophils are characterized by their multi-lobed nucleus and their short lifespan, typically surviving in the bloodstream for only a few hours before migrating into tissues where they carry out their immune functions.