Mast cells

Abstract

Mast cells are found resident in tissues throughout the body, particularly in association with structures such as blood vessels and nerves, and in proximity to surfaces that interface the external environment. Mast cells are bone marrow-derived and particularly depend upon stem cell factor for their survival. Mast cells express a variety of phenotypic features within tissues as determined by the local environment. Withdrawal of required growth factors results in mast cell apoptosis. Mast cells appear to be highly engineered cells with multiple critical biological functions. They may be activated by a number of stimuli that are both Fc epsilon RI dependent and Fc epsilon RI independent. Activation through various receptors leads to distinct signaling pathways. After activation, mast cells may immediately extrude granule-associated mediators and generate lipid-derived substances that induce immediate allergic inflammation. Mast cell activation may also be followed by the synthesis of chemokines and cytokines. Cytokine and chemokine secretion, which occurs hours later, may contribute to chronic inflammation. Biological functions of mast cells appear to include a role in innate immunity, involvement in host defense mechanisms against parasitic infestations, immunomodulation of the immune system, and tissue repair and angiogenesis.

The presence of stromal mast cells identifies a subset of invasive breast cancers with a favorable prognosis

“…Mast cells produce a large number of amines, such as histamine, enzymes including tryptase and chymase, and cell activator molecules, such as the cytokine interleukin-4, that might influence the ability of breast carcinoma cells to invade and metastasize. 12 It is possible, for example, that interleukin-4 produced by mast cells could induce apoptosis of breast cancer cells, so diminishing the rate of growth and metastatic potential of breast carcinoma. 13 Histamine has been shown to promote the growth of breast carcinoma cells in vitro.…”

Endocannabinoids inhibit release of nerve growth factor by inflammation-activated mast cells

“…In this line, an increased number of polymorphonucleate cells are observed in animal models of inflammation [28], and the neurotrophin possesses hyperalgesic properties as assessed by various tests for pain score in laboratory species, as well as in humans. [29][30].…”

Mast cells are permissive for rhinovirus replication: potential implications for asthma exacerbations

“…They are bone marrow‐derived haematopoietic cells, which are classically associated with the early‐phase allergic reaction in asthma 22. In asthma, MC numbers are increased in the bronchial epithelium, submucosal glands and bronchial smooth muscle where they have an activated phenotype 23, 24, 25.…”