FceRI regulation

Kraft S. Kinet JP New developments in FceRI regulation. function and inhibition. Nat Rev Immunol... 

Negative Regulation of FceRI-Dependent Mast Cell Activation... 

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... 

Kalesnikoff J. Rios EJ, Chen CC, Alejandro Barbieri M. Tsai M. Tam SY, Galli SJ Roles of RabGEFl/ Rabex-5 domains in regulating FccRI surface expression and FceRI-dependent responses in mast cells. Blood 2007 109 5308-5317. 

Hamilton RG, Lichtenstein LM Down-regulation of FceRI expression on human basophils during in vivo treatment of atopic patients with anti-IgE antibody. J Immunol 1997 158 ... 

Fujimura Y, Tachibana H, Yamada K. 2004. Lipid raft-associated catechin suppresses the FceRI expression by inhibiting phosphorylation of the extracellular signal-regulated kinasel/2. FEBS Lett 556 204-210. 

FceRII (CD23) receptor plays an important role in regulation of IgE synthesis. In comparison to FceRI, it shows low affinity to IgE. It is found on dendritic cells, macrophages, monocytes, platelets, T and B lymphocytes, and eosinophils. In its soluble form, it sometimes activates B lymphocytes to produce IgE. 

Schroeder, J. T., Bieneman, A. P., Xiao, H. et al. 2005. TLR9- and FceRI-mediated responses oppose one another in plasmacytoid dendritic cells by down-regulating receptor expression, J Immunol 175 5724-5731. 

B. In Vitro Regulation of FceRI on Human Basophils from Treated Subjects... 

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