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Updated: Aug 11, 2026
A Simple and Efficient Method to Isolate Macrophages from Mixed Primary Cultures of Adult Liver Cells
Published on: May 24, 2011
Abstract:
Multinucleated giant cells are commonly found in a wide variety of inflammatory reactions. They are formed at sites of tissue injury by fusion of freshly exuded monocytes, the rate of fusion being dependent on a range of extracellular and intracellular factors. Electron miscroscopy shows that the pooled components of the fused monocytes are not randomly dispersed in the syncytium, but are highly reorganized into a functioning unit. In addition, histochemical and biochemical profiles of cell populations containing these polykarya display a range of metabolic activities, including DNA synthesis, which, on occasions, is followed by successful mitotic division and the formation of polyploid daughter cells. Fusion results in the loss of some surface receptors which in turn interferes with the phagocytic performance of polykarya, which is generally less pronounced than their mononuclear precurses. In addition, polykarya are not as actively motile as macrophages although phenomena of contact inhibition are less obvious. On the other hand, the multinucleate giant cells display prominent exocytosis which may aid in the degradation of extracellular material. The properties of macrophage polykarya contrast with macrophage homokarya produced in vitro. The latter are actively phagocytic, do not synthesize DNA, and have a longer half-life than the syncytia produced in chronic inflammatory reactions. It may well be that the polykarya in such reactions are not true homokarya.
Insights
Multinucleated giant cells form from fused monocytes at injury sites. These cells exhibit unique metabolic activities and functions, differing from their mononuclear precursors.
Area of Science:
- Cell Biology
- Immunology
- Pathology
Background:
- Multinucleated giant cells (MGCs) are prevalent in inflammatory responses.
- They originate from the fusion of monocytes at sites of tissue damage.
Purpose of the Study:
- To investigate the cellular and functional characteristics of MGCs.
- To compare MGCs with mononuclear precursors and in vitro-derived macrophage homokarya.
Main Methods:
- Electron microscopy to examine MGC ultrastructure.
- Histochemical and biochemical analyses to assess metabolic activity.
- Comparison of MGCs with in vitro-generated macrophage homokarya.
Main Results:
- MGCs show reorganized intracellular components and metabolic activity, including DNA synthesis and occasional mitosis.
- Fusion leads to reduced phagocytic capacity and motility compared to mononuclear cells.
- MGCs exhibit prominent exocytosis, potentially aiding in extracellular material degradation.
Conclusions:
- MGCs are complex functional units with distinct properties from their monocyte precursors.
- Their functional characteristics, including reduced phagocytosis and motility, are notable.
- The properties of MGCs in chronic inflammation may differ from true macrophage homokarya.
