Abstract :
The cells of the immune system respond to their environment through an array of signaling receptors. Key among these, are the family of multichain immune recognition receptors (MIRRs), including the T-cell and B-cell receptors, and the high-affinity IgE receptor expressed by mast cells and basophils. These receptors are complexes composed of ligand-binding domains associated with signal-transducing subunits. The biochemical cascades triggered by MIRRs are understood in significant detail, however, the mechanism by which antigen binding initiates signaling is not known. In this Opinion, a novel mechanistic model for the MIRR-mediated signaling is proposed. The model assumes that this process is triggered and controlled by homo-oligomerization of signal-transducing subunits. Principles learned in this model have important implications for immune response in general.
