New inhibitors for expression of IgE receptor on human mast cell.

Exploration for inhibitors against expression of IgE receptor (Fc epsilonRI) on human mast cell, a significant trigger to acute and chronic allergic symptoms, disclosed epigallocatechin gallate (EGCG), epicatechin gallate, and gallocatechin gallate as active principles. Additionally, the anthocyanidin, delphinidin, and the flavone, tricetinidin, possessing a pyrogallol function were also revealed to suppress expression of Fc epsilonRI. Structure-activity relationship analysis among catechins, anthocyanidins, and flavones revealed the pyrogallol moiety to be crucial for biological potency. Furthermore, EGCG was clarified to reduce generation of gamma-chain subunit to suppress expression of Fc epsilonRI on human mast cells.