Logo image
Tim-3 enhances Fc epsilon RI-proximal signaling to modulate mast cell activation
Journal article   Open access   Peer reviewed

Tim-3 enhances Fc epsilon RI-proximal signaling to modulate mast cell activation

Binh L. Phong, Lyndsay Avery, Tina L. Sumpter, Jacob V. Gorman, Simon C. Watkins, John D. Colgan and Lawrence P. Kane
The Journal of experimental medicine, Vol.212(13), pp.2289-2304
12/14/2015
DOI: 10.1084/jem.20150388
PMCID: PMC4689164
PMID: 26598760
url
https://doi.org/10.1084/jem.20150388View
Published (Version of record) Open Access

Abstract

T cell (or transmembrane) immunoglobulin and mucin domain protein 3 (Tim-3) has attracted significant attention as a novel immune checkpoint receptor (ICR) on chronically stimulated, often dysfunctional, T cells. Antibodies to Tim-3 can enhance antiviral and antitumor immune responses. Tim-3 is also constitutively expressed by mast cells, NK cells and specific subsets of macrophages and dendritic cells. There is ample evidence for a positive role for Tim-3 in these latter cell types, which is at odds with the model of Tim-3 as an inhibitory molecule on T cells. At this point, little is known about the molecular mechanisms by which Tim-3 regulates the function of T cells or other cell types. We have focused on defining the effects of Tim-3 ligation on mast cell activation, as these cells constitutively express Tim-3 and are activated through an ITAM-containing receptor for IgE (Fc epsilon RI), using signaling pathways analogous to those in T cells. Using a variety of gain-and loss-of-function approaches, we find that Tim-3 acts at a receptor-proximal point to enhance Lyn kinase-dependent signaling pathways that modulate both immediate-phase degranulation and late-phase cytokine production downstream of Fc epsilon RI ligation.
Immunology Life Sciences & Biomedicine Medicine, Research & Experimental Research & Experimental Medicine Science & Technology

Details

Logo image