As a major event in type Ⅰ allergic reaction,degranulation of mast cells is triggered by the interaction between specific IgEs and high affinity IgE receptors (FcεRIs) on mast cell membrane,and is followed by the release of a battery of inflammatory mediators,such as histamine,leukotrienes and arachidonic acid,and these inflammatory mediators in turn induce a series of allergic symptoms.Recently,Allergin-1 has been found to be an immunoglobulin-like receptor preferentially expressed on mast cells.The crosslinking of Allergin-1 to FcεRIs on mast cells may inhibit the signal transduction from FcεRIs to intracellular immunoreceptor tyrosine-based inhibitory motif (ITIM),generate ITIM inhibitory signals,which then participate in the regulation of mast cell degranulation,and finally block the initiation of allergic inflammation.