Related Experiment Video
Updated: Jun 5, 2026
07:07
Evaluation of T Follicular Helper Cells and Germinal Center Response During Influenza A Virus Infection in Mice
Published on: June 27, 2020
Galectin-9 regulates T helper cell function independently of Tim-3
Ee W Su1, Shuguang Bi, Lawrence P Kane
1Department of Immunology, University of Pittsburgh School of Medicine, BST E-1056, Pittsburgh, PA 15261, USA.
Glycobiology
|December 29, 2010
Summary
Galectin-9 (a protein) can trigger pro-inflammatory cytokine production in T helper cells, independent of the Tim-3 receptor. This reveals a more complex role for galectin-9 in immune responses.
Area of Science:
- Immunology
- Molecular Biology
- Cell Biology
Background:
- Galectin-9 is a member of the galectin family, known for its role as an eosinophil chemoattractant and inducer of apoptosis.
- Galectin-9 binds to Tim-3, a receptor on T cells implicated in limiting immune responses during chronic inflammation, autoimmune diseases, and viral infections.
- The precise contribution of the galectin-9/Tim-3 interaction to these immune modulatory effects remains unclear.
Purpose of the Study:
- To investigate the multifaceted roles of galectin-9 beyond its previously known pro-apoptotic functions.
- To determine if galectin-9 influences T helper cell cytokine production.
- To elucidate the involvement of the Tim-3 receptor in galectin-9-mediated T cell responses.
Main Methods:
- Treated T helper cells with varying concentrations of galectin-9.
- Measured the production of pro-inflammatory cytokines.
- Assessed the necessity of the Tim-3 receptor for galectin-9's effects.
Main Results:
- Galectin-9 induces the production of pro-inflammatory cytokines from T helper cells in a dose-dependent manner.
- This cytokine induction occurs independently of the Tim-3 receptor.
- Galectin-9 exhibits functions beyond apoptosis induction.
Conclusions:
- Galectin-9 possesses a more complex role in modulating T cell responses than previously understood.
- Galectin-9 can activate T helper cells to produce inflammatory cytokines via Tim-3-independent pathways.
- These findings suggest the involvement of additional galectin-9 receptors on T cells.
Related Concept Videos
01:24T Cell Types and Functions
When T cells with CD4 markers are activated, they give rise to two types of effector cells: helper T cells and regulatory T cells. Meanwhile, T cells with CD8 markers differentiate into effector cytotoxic T cells. The differentiation of CD4 T cells into helper T cell subsets, such as Th1, Th2, and Th17 cells, is dependent on the antigen type, antigen-presenting cell, and regulatory cytokines.
Th1 cells stimulate dendritic cells to express necessary co-stimulatory molecules on their surfaces for...
Th1 cells stimulate dendritic cells to express necessary co-stimulatory molecules on their surfaces for...
01:22T Cell Activation and Clonal Selection
T cells are integral to our adaptive immune system, recognizing and effectively responding to foreign antigens. T cell activation and clonal selection are pivotal in orchestrating this immune response. This article elucidates these mechanisms, detailing the roles of cluster of differentiation (CD) markers, major histocompatibility complex (MHC) molecules, costimulatory signals, and the process of clonal selection.
Naive T cells that have not yet encountered an antigen express two primary CD...
Naive T cells that have not yet encountered an antigen express two primary CD...
01:27Cytotoxic T Cells-mediated Immune Response
Cytotoxic T cells are a vital component of the immune system. They have the remarkable ability to identify and target antigens on infected or abnormal cells. These antigens often originate from intracellular pathogens such as viruses or abnormal proteins cancer cells produce.
Immunological surveillance is the ability of immune cells to monitor and eliminate infected cells with intracellular pathogens, neoplastically transformed cells, and cells with non-self antigens. Cytotoxic T cells and NK...
Immunological surveillance is the ability of immune cells to monitor and eliminate infected cells with intracellular pathogens, neoplastically transformed cells, and cells with non-self antigens. Cytotoxic T cells and NK...
01:30General Transcription Factors
Tissue-specific transcription factors contribute to diverse cellular functions in mammals. For example, the gene for beta globin, a major component of hemoglobin, is present in all cells of the body. However, it is only expressed in red blood cells because the transcription factors that can bind to the promoter sequences of the beta globin gene are only expressed in these cells. Tissue-specific transcription factors also ensure that mutations in these factors may impair only the function of...
01:15Receptor Downregulation in MVBs
Multivesicular bodies (MVBs) are mature endosomes that sort ubiquitinated proteins and then fuse with lysosomes to degrade the sorted proteins. Epidermal growth factor (EGF) and its receptor (EGFR) form a complex that can be internalized through endocytosis, sorted into an MVB, and later degraded.
The EGFR can initiate signaling pathways that lead to cell proliferation, migration, and differentiation. Overexpression of EGFR stimulates cells to proliferate. Excessive EGFR activation may...
The EGFR can initiate signaling pathways that lead to cell proliferation, migration, and differentiation. Overexpression of EGFR stimulates cells to proliferate. Excessive EGFR activation may...