A giant cell (also known as a multinucleated giant cell, or multinucleate giant cell) is a mass formed by the union of several distinct cells (usually histiocytes), often forming a granuloma.[1]
Although there is typically a focus on the pathological aspects of multinucleate giant cells (MGCs), they also play many important physiological roles. Osteoclasts are a type of MGC that are critical for the maintenance, repair, and remodeling of bone and are present normally in a healthy human body. Osteoclasts are frequently classified and discussed separately from other MGCs which are more closely linked with disease.
Non-osteoclast MGCs can arise in response to an infection, such as tuberculosis, herpes, or HIV, or as part of a foreign body reaction. These MGCs are cells of monocyte or macrophage lineage fused together. Similar to their monocyte precursors, they can phagocytose foreign materials. However, their large size and extensive membrane ruffling make them better equipped to clear up larger particles. They utilize activated CR3s to ingest complement-opsonized targets. Non-osteoclast MGCs are also responsible for the clearance of cell debris, which is necessary for tissue remodeling after injuries.[2]
Types include foreign-body giant cells, Langhans giant cells, Touton giant cells, Giant-cell arteritis
- ^ Giant+Cells at the U.S. National Library of Medicine Medical Subject Headings (MeSH)
- ^ Milde R, Ritter J, Tennent GA, Loesch A, Martinez FO, Gordon S, et al. (December 2015). "Multinucleated Giant Cells Are Specialized for Complement-Mediated Phagocytosis and Large Target Destruction". Cell Reports. 13 (9): 1937–1948. doi:10.1016/j.celrep.2015.10.065. PMC 4675895. PMID 26628365.