Mystery mast cells under scanner again

Mast Cells are the most neglected immune cells to be studied yet are the most important amongst them. They are the classical mediators of allergic reactions. When the antigen-specific IgE binds to an antigen (usually allergen), it triggers mast cell activation by binding to high-affinity Fc epsilon receptor I. This leads to the release of mast cell mediators such as histamine, chymotryptase, tryptase, TNF etc. To protect the mast cells from activation induced death, the CD200R is induced. CD200R inhibits mast cell activation through ITIM (immunoreceptor tyrosine-based inhibition motif ).

Recent evidence shows that Mast cellos sense pathogens through toll-like receptor mediated pathways. In addition, the receptors for IgG2a and Ig light chains have been identified. However, the receptor for IgLC is yet to be characterised. Added to this is the concept of MCregs (regulatory mast cells). Mast cells are identified in the triumvirate along with Tregs and Th17. While the tregs inhibit mast cells, mast cells in turn activate the Th17 cells. The complete mechanisms underlying this three-way interactions is to be explore.