title: Morphological analysis of multinucleated giant cells occurred in experimental autoimmune myocarditis.
abstract: Our previous study reported the rich existence of multinucleated giant cells in an autoimmune myocarditis experimentally induced in rats. The present study investigated the histochemical and ultrastructural characteristics of these giant cells. Histochemistry for an acid phosphatase clearly demonstrated multinucleated giant cells dispersed at the inflammatory foci. Ultrastructurally, the giant cells were shown to be single cells, but not clustered cells. Their ultrastructural characteristics were very similar to the basic features of macrophages, except that the giant cells were poor in lysosomes and phagosomes. It was noticeable that some macrophages possessed three or more nuclei, displaying an intermediate form between mononuclear macrophages and multinucleated giant cells. These findings suggest that the giant cell in the experimental autoimmune myocarditis is a single multinucleated cell, and possibly derived from macrophages by cell-to-cell fusion.
authors.affiliation: First Department of Internal Medicine, Niigata University School of Medicine, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Saeki
authors.forename: H
authors.initials: H
authors.lastname: Takahashi-Iwanaga
authors.forename: T
authors.initials: T
authors.lastname: Iwanaga
authors.forename: T
authors.initials: T
authors.lastname: Fujita
authors.forename: M
authors.initials: M
authors.lastname: Kodama
authors.forename: H
authors.initials: H
authors.lastname: Hanawa
authors.forename: S
authors.initials: S
authors.lastname: Zhang
authors.forename: T
authors.initials: T
authors.lastname: Izumi
authors.forename: A
authors.initials: A
authors.lastname: Shibata
mesh_terms: D000135:Acid Phosphatase / Q000378:metabolism; D000818:Animals; D001327:Autoimmune Diseases / Q000139:chemically induced / Q000473:pathology*; D002459:Cell Fusion; D004195:Disease Models, Animal; D015726:Giant Cells / Q000201:enzymology / Q000648:ultrastructure*; D008264:Macrophages / Q000648:ultrastructure; D008297:Male; D009205:Myocarditis / Q000139:chemically induced / Q000473:pathology*; D051381:Rats; D011917:Rats, Inbred Lew
chemical_list: D000135:Acid Phosphatase