Mast cells expression

Mast cells express high-affinity IgE Fc receptors (FceRI) on their surface, contain cytoplasmic granules which are major sources of histamine and other inflammatory mediators, and are activated to release and generate these mediators by IgE-dependent and non-IgE-dependent mechanisms [1]. Disturbances either in the release of mast cell mediators or in mast cell proliferation are associated with clonal mast cell disorders including monoclonal mast cell activation syndrome (MMAS) and mastocytosis respectively, which are in turn associated with some cases of anaphylaxis [2], Molecular mechanisms have been identified which may link increased releasability of mast cell mediators and conditions leading to increased mast cell numbers [3]. Patients with mastocytosis have an increased risk to develop anaphylaxis [4, 5] and those with anaphylaxis may suffer from unrecognized mastocytosis or may display incomplete features of the disease [6-8]. 

Facci L, Dal Toso R, Romanello S, Buriani A, Skaper SD, Leon A. Mast cells express a peripheral cannabinoid receptor with differential sensitivity to anandamide and palmitoylethanolamide. Proc Natl Acad Sci USA 1995 92 3376-3380. 

Cao, J., Papadopoulou, N., Kempuraj, D., Boucher, W.S., Sugimoto, K., Cetrulo, C.L., and Theoharides, T.C. 2005. Human mast cells express corticotropin-releasing hormone (CRH) receptors and CRH leads to selective secretion of vascular endothelial growth factor. J Immunol 174 7665-7675. 

Maggi E, et al. Tryptase-chymase double-positive human mast cells express the eotaxin receptor CCR3 and are attracted by CCR3-binding chemokines. Am. J. Pathol. 1999 155 1195-1204. 

K., Lowhagen, O., Kay, A.B. and Hamid, Q.A. (1994). T lymphocytes and mast cells express messenger RNA for interleukin-4 in the nasal mucosa in allergen-induced rhinitis. Immunology 82, 200-206. 

IL-3 is produced by T lymphocytes, but also by mast cells. In rodents it is important for the development of mast cells and basophils and promotes eosinophil survival (Wasserman, 1990). Antibodies to IL-3 result in a fall in tissue numbers of mast cells in mice. IL-3 has been repotted to protect mast cells from apoptosis, an event likely mediated by the maintenance of intracellular calcium levels (Mekori et al., 1993). Whether IL-3 plays a critical role in mast cell expression in human tissues is not clear and other cytokines including IL-10 and stem cell ffictor c-kit ligand) may also be important. 

Histamine is in mast cells, basophils, and platelets. Human skin mast cells express H H2, and H4 receptors, but not H3 receptors. Hi and H2 receptors are involved in wheal formation and erythema, whereas only Hi-receptor agonists cause pruritus. Complete blockade of Hi-receptors does not totally relieve itching, and combinations of Hi and H2 blockers may be superior to H, blockers alone. 

Fig. 3.5 Amplification of IgE antibody production by B cells by direct interaction of mast cells expressing CD40L and secreting IL-4. These interact with...

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