Exposure of RBL-2H3 Mast Cells to Ag+ Induces Cell Degranulation and Mediator Release
Authors: Suzuki Y.1; Yoshimaru T.1; Yamashita K.1, 2; Matsui T.1, 2; Yamaki M.2; Shimizu K.1
Source: Biochemical and Biophysical Research Communications, Volume 283, Number 3, May 2001 , pp. 707-714(8)
Publisher: Academic Press
Abstract:
There is a growing need to understand the impact of environmental sulfhydryl group-reactive heavy metals on the immune system. Here we show that Ag+ induces mast cell degranulation, as does the aggregation of the high affinity immunoglobulin E receptor (Fc
RI). Micromolar quantities of Ag+ specifically induced degranulation of mast cell model rat basophilic leukemia (RBL-2H3) cells without showing cytotoxicity. The Ag+-mediated degranulation could be observed as rapidly as 5 min after the addition of the ions. Ag+ also induced a rapid change in tyrosine phosphorylation of multiple cellular proteins including the focal adhesion kinase but not Syk kinase. The Syk-selective inhibitor piceatannol and the Src family-selective tyrosine kinase inhibitor PP1 dose-dependently inhibited Fc
RI-mediated degranulation, whereas neither compound inhibited the Ag+-mediated degranulation. Furthermore, likewise Fc
RI aggregation, Ag+ also induced leukotriene secretion. These results show that Ag+ activates RBL-2H3 mast cells through a tyrosine phosphorylation-linked mechanism, which is distinct from that involved in Fc
RI-mediated activation. Copyright 2001 Academic Press.
Keywords: RBL-2H3 cells; silver ions; cell degranulation; leukotriene secretion; tyrosine phosphorylation
Language: English
Document Type: Research article
Affiliations: 1: Department of Immunology and Microbiology, Nihon University School of Medicine, Tokyo, 173-8610, Japan 2: Pharmaceutical Research Laboratory, Hitachi Chemical Company, Ltd., Ibaraki, 317-8555, Japan

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