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Which white blood cells arrive first at a site of acute inflammation?
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inflammation
The main function of complement proteins is to aid in the destruction of pathogens by piercing their outer membranes (cell lysis) or by making them more attractive to phagocytic cells such as macrophages (a process known as opsonization). Some complement components also promote inflammation by stimulating cells to release histamine and by attracting phagocytic cells to the site of infection.
Neutrophils are the white blood cells that arrive first at a site of acute inflammation. These phagocytes can reach the area of injury or infection within an hour, guided by chemical signals through a process known as chemotaxis.12
While neutrophils are the primary responders, monocytes—which later mature into macrophages—typically arrive at the site 24 to 48 hours after the inflammatory process begins.1