Membrane Receptor Clustering as a Cellular Stimulus — The Mast Cell Case

Abstract

The secretory response of the mast cell to clustering of its surface membrane receptors for Fc_ε domains of IgE (Type 1 Fc_ε receptors — Fc_εRI) has long been recognized as an instructive paradigm for stimulus-secretion coupling mechanisms (Froese 1984; Metzger et al 1986; Siraganian 1988). Moreover, since the initial triggering event is the specific antibody-antigen reaction taking place at the cell-surface, it provides an excellent model system for the diversity of cellular activation processes encountered in the immune system where the interaction between antigen receptors and their polyvalent ligands is the very first event (cf. De Lisi 1980). Mainly two features make mast cells useful and informative; a rather fast response which can be quantitated with relative ease and the availability of at least one cell-line (Barsumian et al 1981) accessible to biophysical and biochemical studies.