Bridget S. Wilson

Regulation and Roles of the Membrane, Cytoskeletal and Adhesive Responses of RBL-2H3 Rat Tumor Mast Cells to FcεRI Crosslinking

Mast cells, basophils and RBL-2H3 rat tumor mast cells are activated by treatments that crosslink their high affinity IgE receptor, FceRI. Receptor crosslinking causes degranulation, releasing inflammatory agents that initiate the immediate hypersensitivity diseases including allergy, asthma and anaphylaxis. Receptor crosslinking also stimulates the production of lipid mediators that amplify the immediate inflammatory response and of cytokines that maintain inflammation through the recruitment and activation of other pro-inflammatory cells. Additionally, FceRI crosslinking induces a series of immediate and dramatic changes in the membrane, cytoskeletal and adhesive properties of basophils and mast cells that are the subject of this chapter.

Time-Resolved 3D Tracking of Individual Quantum Dot Labeled Proteins in Live Cells via Confocal Feedback

We have developed a microscope system that uses active feed-back to follow individual quantum dot labeled proteins moving in three dimensions in live cells at μm/s transport velocities with 100 picoseconds temporal resolution.

Phosphoinositide-Derived Second Messengers in FcεRI Signaling: PI-3 Kinase Products Control Membrane Topography and the Translocation and Activation of PLC-γ1 in Antigen-Stimulated Mast Cells

In mast cells and basophils, cross-linking the high-affinity IgE receptor, FceRI, leads to the secretion of histamine and other granule constituents, to changes in adhesive properties, cell shape, and surface topography, and to the synthesis of lipid mediators of inflammation and of cytokines. Key features of this signaling cascade were summarized by contributors to an earlier volume1 and are updated in other chapters in this volume. In brief, cross-linking IgE-bound receptors with multivalent ligands activates receptor-associated Lyn, a member of the Src tyrosine kinase family whose principal mast cell substrates are immunoreceptor tyrosine-based activation motifs (ITAMs) found in the FceRI γ- and β-subunit cytoplasmic domains.2–4 Lyn-mediated receptor subunit phosphorylation in turn permits the recruitment and activation of Syk tyrosine kinase5 and the phosphorylation of multiple protein substrates.6