activated macrophage

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ac·ti·vat·ed mac·ro·phage

a mature macrophage, in an active metabolic state, that is cytotoxic to tumor/target cells, usually following exposure to certain cytokines.
Synonym(s): armed macrophage

activated macrophage

A mononuclear phagocyte that has been “turned on”—i.e., has enhanced activity by cytokines. Activated macrophages (AMs) are twice the size of resting macrophages and more aggressive (increased lysozymes and surface expression of MHC class-II antigens), and are pivotal in defending a host against microorganisms that grow well within histiocytes/tissue-based macrophages and other cells—e.g., Listeria spp, and Salmonella spp.

activated macrophage

Immunology A mononuclear phagocyte that has been 'turned on'–ie has enhanced activity by cytokines; AMs are bigger–twice the size of resting macrophages and 'badder'–↑ lysozymes and surface expression of MHC class II antigens, and are pivotal in defending against microorganisms that grow well in histiocytes/tissue-based macrophages and other cells–eg, Listeria spp, and Salmonella spp


any of the large, mononuclear, highly phagocytic cells derived from bone marrow cells, promonocytes, the progeny of which, the monocytes, enter the bloodstream, where they stay for a few days before entering the tissues and developing into macrophages. They are components of the monocyte-macrophage system. Macrophages are usually immobile but become actively mobile when stimulated by inflammation, immune cytokines and microbial products. They are an important class of antigen presenting cells (APCs). See also immunity.

activated macrophage
under the influence of cytokines, particularly γ-interferon and interleukin 4, released by antigen-stimulated Th1 lymphocytes, resting macrophages are activated whereby they become larger, more motile, stickier, express more MHCII proteins on their surface, contain more lysosomes and lysosomal enzymes, and secrete a variety of substances including interleukin 1, tumor necrosis factors; they have increased phagocytic activity and increased killing via reactive oxygen intermediates, collagenases and lysosomal enzymes. Called also angry macrophage.
macrophage activating factor (MAF)
a lymphokine produced by T lymphocytes following in vitro, probably γ-interferon, antigenic stimulation that activates macrophages.
alveolar m's
rounded, granular, mononuclear phagocytes within the alveoli of the lungs that ingest inhaled particulate matter.
angry macrophage
see activated macrophage (above).
armed m's
those capable of inducing cytotoxicity as a consequence of binding antibodies via Fc receptors on their surfaces or by factors derived from T lymphocytes (specific macrophage arming factor [SMAF]).
macrophage chemotactic factor (MCF)
a lymphokine that attracts macrophages.
macrophage colony-stimulating factor
see colony-stimulating factors.
macrophage inhibition factor (MIF)
a lymphokine that inhibits macrophage migration, causing them to accumulate at the site of antigen.
specific macrophage arming factor (SMAF)
a lymphokine that stimulates macrophage cytotoxic activity.
References in periodicals archive ?
Nachshon Knoller, Senior Neurosurgeon, Sheba Medical Center, Tel Hashomer, Israel, a principal investigator in this study commented, "In view of the impressive published preclinical results obtained with autologous activated macrophages, I am pleased to have performed the first such human procedure to test the safety of the technique.
An abundantly secreted glycoprotein from Drosophila melanogaster is related to mammalian secretory proteins produced in rheumatoid tissues and by activated macrophages.
Galectin-3 marks activated macrophages in failure-prone hypertrophied hearts and contributes to cardiac dysfunction.
Murine gamma herpes virus induced fibrosis is associated with the development of alternatively activated macrophages.
As discussed above, macrophages could act as the key immune-competent and immune- regulator cells in host defense by affecting immune parameters via numerous cytokines such as IL-1[beta], IL-6, IFN-[gamma] and TNF-[alpha] to promote the proliferation and differentiation of immune cells, as well as releasing moderate production of NO from the expression of iNOS in activated macrophages to kill pathogens or tumor cells under the appropriate immune stimulant from the environment (Karupiah et al.
The hormone is released from activated macrophages in pulmonary alveoli with granulomatous inflammation (16).
Most of the time when you encounter activated macrophages in the CNS, they're contributing to local inflammation, dysfunction, and disease," notes William Hickey of Dartmouth Medical School in Lebanon, N.
Activated macrophages are responsible for stripping myelin from axons in the CNS, ie, the destruction phase of the DTH reaction in MS.
A third cytokine called tumor necrosis factor (TNF), which is made and released by activated macrophages, is reportedly toxic to oligodendrocytes--the cells that make myellin--and causes demyelination.
YKL-40, a new biomarker of inflammation, is secreted by activated macrophages and neutrophils in different tissues with inflammation (5, 6).
The PAPP-A measured in the circulation during pregnancy is produced by the syncytiotrophoblast and is different from the PAPP-A that is present in atherosclerotic plaques and is produced by fibroblasts, vascular smooth muscle cells, and activated macrophages.
Together the activated macrophages, B lymphocytes, and antibodies form granulomas in the affected tissue.

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