Mast cells degranulation

Asthma is a complex respiratory disorder that involves mast cell degranulation, mucous secretions, and smooth muscle hypertrophy and hyperresponsiveness. Smooth muscle hyperresponsiveness has suggested some defect in the regulation of smooth muscle contractility. Therefore, a number of studies concerning asthma have centered on whether alterations in the regulation of smooth muscle contraction (Figure 4) are responsible for hyperactivity in asthmatic airway smooth muscle. 

Downstream of early FceRI-induced signaling events (such as Ca + influx), the final stages of mast cell degranulation require membrane fusion events. The exocytosis of... 

Adding another layer of complexity to the regulation of mast cell activation levels in vivo is the observation that activated mast cells can respond to, and in some cases produce, a myriad of mediators that may serve to amplify FceRI-induced responses. For example, stem cell factor (SCF), the ligand for KIT, both can enhance FceRI-dependent activation of mouse or human mast cells and, under certain circumstances, can directly induce mast cell degranulation [6, 25, 62]. Thus, elevated SCF levels and/or activating KIT mutations (such as those that occur in mastocytosis) may exacerbate mast cell-driven reactions. Indeed, patients (both adult and children) with extensive skin disease associated with mastocytosis are at increased risk to develop severe anaphylaxis [63]. Moreover, it was recently reported that cases of idiopathic anaphylaxis are... 

Galli SJ, Kinet JP Absence of FceRI a chain results in upregulation of FcyRIII-dependent mast cell degranulation and anaphylaxis. Evidence of competition between FceRI and FcyRIII for limiting amounts of FcR (3 and y chains. J Clin Invest 1997 32 99 915-925. 

Kinet JP, GaUi SJ Systemic anaphylaxis in the mouse can be mediated largely through IgGl and FcyRIII. Assessment of the cardiopulmonary changes, mast cell degranulation, and death associated with active 35 or IgE- or IgGl-dependent passive anaphylaxis. J Clin Invest 1997 99 901-914. 

Suzuki K. Verma IM Phosphorylation of SNAP-23 by IkB kinase 2 regulates mast cell degranulation. Cell 2008 134 485-495. 

Leung WH, Holland S The inositol 5 -phosphatase SHIP-2 negatively regulates IgE-induced mast cell degranulation and cytokine production. J Immunol 2007 179 95-102. 

Physical factors, such as heat, mechanical stimulation and exercise, may sometimes lead to mast cell degranulation and whealing in the skin, but rarely provoke systemic anaphylaxis [4, 26]. Patients do report that these and other factors in combination (such as exercise, heat and alcohol) may elicit anaphylaxis in summation. 

Tkaczyk C, Horej si V, Iwaki S, et al NTAL phosphorylation is a pivotal link between the signaling cascades leading to human mast cell degranulation following Kit activation and Fc epsilon RI aggregation. Blood 2004 104 207-214. 17... 

Th2 lymphocytes are one of the primary factors initiating and perpetuating the inflammatory response.7 In addition, proinflammatory mediators such as the leukotrienes generated during mast cell degranulation can increase vascular permeability, leading to airway edema and increased mucus production.8 Eosinophilic infiltration of the airways is a hallmark of asthma, and activated eosinophils can cause bronchoconstriction and AHR.9... 

Inamura, N., Mekori, Y.A., Bhattacharyya, S.P., Bianchine, P.J. and Metcalfe, D.D. (1998) Induction and enhancement of FcERI-dependent mast cell degranulation following coculture with activated T cells dependency on ICAM-1- and leukocyte function-associated antigen (LFA)-l-mediated heterotypic aggregation. Journal of Immunology 160, 4026-4033. 

Most of the itching or rash reported with the opioids is due to histamine release and mast cell degranulation, not to a true allergic response. 

It prevents antigen-triggered mast cell degranulation and release of mediators, including histamine. 

Mast cell degranulation in response to allergens results in release of mediators such as histamine eosinophil, and neutrophil chemotactic factors leukotrienes C4, D4, and E4 prostaglandins and platelet-activating factor (PAF). Histamine is capable of inducing smooth muscle constriction and bronchospasm and may play a role in mucosal edema and mucus secretion. 

Rodgers, K. and Xiong, S., Effect of administration of malathion for 90 days n macrophage function and mast cell degranulation, Toxicol. Lett., 93, 73, 1997. 

Dynorphin, a-neoendorphin and /1-endorphin each produced a dose-dependent (10 6 M to 10 4 M) release of histamine from rat peritoneal mast cells but not from rat mucosal mast cells which were isolated following collagenase digestion [128]. When administered intradermally to the forearms of human volunteers, dynorphin, /f-endorphin, Leu-enkephalin and morphiceptin each produced a wheal and flare reaction at nM concentrations. Mast cell degranulation was confirmed by electron microscopy of biopsy samples and by its inhibition by hyroxyzine pretreatment [129]. 

Recently, BN 52063 has been demonstrated to be effective against mastocytosis [304], a condition which was previously incurable. This suggests that PAF, as well as mast cell degranulation, may have a role in systemic mastocytosis. The injectable (pure) form of BN 52021 is much more powerful than BN 52063. Preliminary clinical investigations have shown a long and intense inhibition of ex vivo PAF-induced platelet aggregation. The injectable form is now under clinical trials in graft rejection, stroke, haemodialysis and shock. 

The interaction of antibody-antigen complexes with cells of the immune system results in the activation of a variety of responses ranging from ADCC, mast-cell degranulation, lymphocyte proliferation, antibody secretion and phagocytosis. All these processes are activated via the binding of the Fc domain of the antibody molecule, which is exposed during antibody-... 

Damen, J.E. Ware, M.D., Kalesnikoff, J., Hughes, M.R. and Krystal, G., 2001, SHIP S C terminus is essential for ist hydrolysis of P1P3 and inhibition of mast cell-degranulation. 

Doherty JM, Streilein JW Hapten-specific tolerance induced by acute, low-dose ultraviolet B radiation of skin requires mast cell degranulation. Eur J Immunol 2001 31 1736-1746. 

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