Related Experiment Video
Updated: Apr 21, 2026

A Microplate Assay to Assess Chemical Effects on RBL-2H3 Mast Cell Degranulation: Effects of Triclosan without Use of an Organic Solvent
Published on: November 1, 2013
Involvement of class II phosphoinositide 3-kinase α-isoform in antigen-induced degranulation in RBL-2H3 cells
Kiyomi Nigorikawa1, Kaoru Hazeki1, Ying Guo1
1Graduate School of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan.
Abstract:
In this study, we present findings that suggest that PI3K-C2α, a member of the class II phosphoinositide 3-kinase (PI3K) subfamily, regulates the process of FcεRI-triggered degranulation. RBL-2H3 cells were transfected with shRNA targeting PI3K-C2α. The knockdown impaired the FcεRI-induced release of a lysosome enzyme, β-hexosaminidase, without affecting the intracellular Ca2+ mobilization. The release of mRFP-tagged neuropeptide-Y, a reporter for the regulated exocytosis, was also decreased in the PI3K-C2α-deficient cells. The release was increased significantly by the expression of the siRNA-resistant version of PI3K-C2α. In wild-type cells, FcεRI stimulation induced the formation of large vesicles, which were associated with CD63, a marker protein of secretory granules. On the vesicles, the existence of PI3K-C2α and PtdIns(3,4)P2 was observed. These results indicated that PI3K-C2α and its product PtdIns(3,4)P2 may play roles in the secretory process.
Related Concept Videos
IP3/DAG Signaling Pathway
B Cell Activation and Differentiation
When naive B cells encounter a specific antigen that can bind to the B cell receptor (BCR) on their surface, they undergo sensitization to respond to the antigen's presence. Sensitization begins with...
Acute Inflammation I: Cellular Phase
Intracellular Signaling Affects Focal Adhesions
Some...

