Phagocytes.
Phagocytes "eat" invading organisms and include 1) the neutrophil, which is the most common type--it usually attacks bacteria; 2) the monocyte, which is the largest type--it plays several roles in immunity; 3) the macrophage, which patrols for pathogens and removes dead and dying cells; and 4) the mast cell, which helps heal wounds and defends against pathogens.
Activation of the superoxide-producing
phagocyte NADPH oxidase requires co-operation between the tandem SH3 domains of p47phox in recognition of a polyproline type II helix and an adjacent alpha-helix of p22phox.
Chronic granulomatous disease is a rare inherited disorder characterised by inability of
phagocytes to generate reactive oxygen species needed for intracellular killing of phagocytosed microorganisms.
Milk fat globule epidermal growth factor 8 (MFG-E8), a protein expressed mainly by activated macrophages and immature dendritic cells, is required for the phagocytosis of apoptotic cells as it links externalized phosphatidylserine present on the surface of apoptotic cells with integrins expressed on
phagocytes (3).
What can we find in nature to change the course so that
phagocytes can operate as they were intended?
Histocytes and
phagocytes were occasionally found in one patient and clearly seen in seven patients.
Key players are the complement system and professional
phagocytes.
The
phagocyte system and disorders of granulopoiesis and granulocyte function.
Monocytes, macrophages and neutrophils are professional
phagocytes; however other cells can perform phagocytosis so that the cell requires the detection of the foreign particle through membrane receptors.