Mast cells are thought to participate in a variety of immune responses, such as parasite resistance and the allergic reaction. Mast cell development depends on stem cell factor (Kit ligand) and its receptor, c-Kit. Gab2 is an adaptor molecule containing a pleckstrin homology domain and potential binding sites for SH2 and SH3 domains. Gab2 is phosphorylated on tyrosine after stimulation with cyt...

Mast cells play an important role in the pathogenesis of allergic diseases. Immature mast cells migrate into peripheral tissues from the bone marrow and undergo complete maturation. Interestingly, mast cells have characteristics similar to hematopoietic stem cells (HSCs), such as self-renewal and c-kit expression. In HSCs, Wnt signaling is involved in their maintenance and differentiation. On t...

The normal human epidermal growth factor receptor (EGF-R) (HERc), a chimeric EGF-R/v-erbB (HERerbB) receptor, and the ligand-independent oncogenic EGF-R variant (v-erbB) were used to correct the mast cell defects in W/Wv bone marrow (BM) cells. In culture, all three receptor molecules transduced functional mitogenic signals in infected interleukin-3 (IL-3)-dependent bone marrow-derived mast cel...

Immunoglobulin (Ig)E-mediated activation of mast cells has long been thought to occur only when Fc(epsilon)RI receptor-bound IgE is cross-linked via multivalent antigens. However, recent studies have raised the possibility that mast cells may be activated by the binding of IgE to the Fc(epsilon)RI receptor in the absence of antigen. Here we demonstrate that IgE binding without antigen induces t...

Mast cells are critical effector cells in the pathophysiology of allergic asthma and other IgE-mediated diseases. The Tec family of tyrosine kinases Itk and Btk serve as critical signal amplifiers downstream of antigen receptors. Although both kinases are expressed and activated in mast cells following FcεRI stimulation, their individual contributions are not clear. To determine whether these k...

Activation of mast cells by aggregation of the high-affinity IgE receptors (FcεRI) initiates signaling events leading to the release of inflammatory and allergic mediators stored in cytoplasmic granules. A key role in this process play changes in concentrations of intracellular Ca(2+) controlled by store-operated Ca(2+) entry (SOCE). Although microtubules are also involved in the process leadin...

OBJECTIVE Extracellular ATP mediates mast cell-dependent intestinal inflammation via P2X7 purinoceptors. We have previously shown that CD300f (also called the leucocyte mono-immunoglobulin-like receptor 3 (LMIR3)) suppresses immunoglobulin E-dependent and mast cell-dependent allergic responses by binding to ceramide. The aim of the present study was to clarify the role of ceramide-LMIR3 interac...

Transplantation of autologous bone marrow mononuclear cells (BMMCs) has been proven safe in animal and human studies. However, there are very few studies in stroke patients. In this study, intra-arterial autologous BMMCs were infused in patients with moderate to severe acute middle cerebral artery infarcts. The subjects of this study included 20 patients with early or late spontaneous recanali...

Essential thrombocythemia (ET) is a clonal myeloproliferative disorder characterized by overproduction of megakaryocytes (MKCs) and platelets. The recent discovery of the JAK2 mutation has shed a new light on the development of ET but its pathogenesis still remains unknown. One of the possible mechanisms can be deregulation of apoptosis, resulting in accumulation of bone marrow MKCs. In this st...

Accumulating evidence has indicated that mast cells can modulate a wide variety of immune responses. Migration and adhesion play a critical role in regulation of tissue mast cell function, in particular, under inflammatory conditions. We previously demonstrated that prostaglandin (PG) E(2) stimulates adhesion of a mouse mastocytoma cell line, P-815, to the Arg-Gly-Asp (RGD)-enriched matrix thro...