Histiocyte
Histiocyte | |
---|---|
Details | |
System | Immune system |
Identifiers | |
Latin | macrophagocytus immobilis |
MeSH | D006644 |
TH | H2.00.03.0.01009 |
FMA | 84642 83585, 84642 |
Anatomical terms of microanatomy |
A histiocyte is a vertebrate cell that is part of the mononuclear phagocyte system (also known as the reticuloendothelial system or lymphoreticular system). The mononuclear phagocytic system is part of the organism's immune system. The histiocyte is a tissue macrophage[1] or a dendritic cell[2] (histio, diminutive of histo, meaning tissue, and cyte, meaning cell). Part of their job is to clear out neutrophils once they've reached the end of their lifespan.
Development
Histiocytes are derived from the
However, the term histiocyte has been used for multiple purposes in the past, and some cells called "histocytes" do not appear to derive from monocytic-macrophage lines.[3] The term Histiocyte can also simply refer to a cell from monocyte origin outside the blood system, such as in a tissue (as in rheumatoid arthritis as palisading histiocytes surrounding fibrinoid necrosis of rheumatoid nodules).
Some sources consider Langerhans cell derivatives to be histiocytes.[4] The Langerhans cell histiocytosis embeds this interpretation into its name.
Structure
Histiocytes have common
).Macrophages and dendritic cells
These histiocytes are part of the immune system by way of two distinct functions: phagocytosis and antigen presentation. Phagocytosis is the main process of macrophages and antigen presentation the main property of dendritic cells (so called because of their star-like cytoplasmic processes).
- Macrophages are highly variable in size and morphology, their lysosomes – in relation to their specialised phagocytic function. They express CD68.
- Dendritic cells have an indented (bean-shaped) nucleus and cytoplasm with thin processes (dendritic). Their main activity is antigen presentation; they express Factor XIIIa, CD1c, and Class II Human leukocyte antigens.
Langerhans cells
A subset of cells differentiates into
Clinical significance
See also
References
- .
- PMID 21030305.
- ^ "S12C3-Granuloma". Retrieved 2009-01-06.
- PMID 7524755.
- PMID 9039734.