Related Experiment Video
Updated: May 3, 2026

Mouse Naïve CD4+ T Cell Isolation and In vitro Differentiation into T Cell Subsets
Published on: April 16, 2015
Inducible costimulator facilitates T-dependent B cell activation by augmenting IL-4 translation
Mathieu Gigoux1, Amanda Lovato1, Julien Leconte2
1Institut de recherches cliniques de Montréal (IRCM), Montréal, QC H2W 1R7, Canada; Department of Microbiology and Immunology, McGill University, Montréal, QC H3A 2B4, Canada.
Abstract:
The inducible costimulator (ICOS) is highly expressed in follicular helper T (Tfh) cells, a subset of CD4 T cells that migrate into the B cell zone and facilitate germinal center reactions. Although ICOS is known to play a critical role in forming the Tfh cell population during immune responses, its contribution to the effector functions of Tfh cells remains unclear. Using activated mouse splenic CD4 T cells we demonstrate that ICOS assists TCR-mediated signal transduction by potentiating the PI3K-AKT-mTOR signaling cascade that leads to hyper-phosphorylation of p70S6K and 4E-BP1, events that are known to augment cap-dependent mRNA translation. Consequently, ICOS costimulation promotes the formation of polysomes on IL-4 mRNA in a PI3K-dependent manner. Furthermore, we show that the supply of IL-4 becomes a limiting factor for T-dependent B cell activation during in vitro co-culture when the ICOS-PI3K signaling axis is disrupted in T cells. This ICOS costimulation-dependent translational control may ensure targeted delivery of IL-4 to cognate B cells during T-B collaborations in the germinal center.
More Related Videos
06:16Generation of Orthotopic Pancreatic Tumors and Ex vivo Characterization of Tumor-Infiltrating T Cell Cytotoxicity
Published on: December 7, 2019
07:34Induction of Intestinal Inflammation by Adoptive Transfer of CBir1 TCR Transgenic CD4+ T Cells to Immunodeficient Mice
Published on: December 16, 2021
Related Concept Videos
T Cell Activation and Clonal Selection
Naive T cells that have not yet encountered an antigen express two primary CD...
T Cell Types and Functions
Th1 cells stimulate dendritic cells to express necessary co-stimulatory molecules on their surfaces for...
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...
The JAK-STAT Signaling Pathway
TGF - β Signaling Pathway
NF-κB-dependent Signaling Pathway
NF-κB-dependent Signaling Mechanism
The...