Related Experiment Video

Updated: Aug 8, 2026

Using an Automated Cell Counter to Simplify Gene Expression Studies: siRNA Knockdown of IL-4 Dependent Gene Expression in Namalwa Cells
10:34

Using an Automated Cell Counter to Simplify Gene Expression Studies: siRNA Knockdown of IL-4 Dependent Gene Expression in Namalwa Cells

Published on: April 14, 2010

IL-4-activated STAT-6 inhibits IFN-gamma-induced CD40 gene expression in macrophages/microglia

V T Nguyen1, E N Benveniste

  • 1Department of Cell Biology, University of Alabama, Birmingham, AL 35294, USA.

Journal of Immunology (Baltimore, Md. : 1950)
|November 22, 2000
PubMed

Insights

Interleukin-4 (IL-4) suppresses interferon-gamma (IFN-gamma)-induced CD40 expression by binding to specific sites on the CD40 promoter via STAT-6. This clarifies how IL-4 inhibits IFN-gamma

Area of Science:

  • Immunology
  • Molecular Biology
  • Gene Regulation

Background:

  • Cytokine antagonism between IFN-gamma and IL-4 is known, but IL-4's mechanism for inhibiting IFN-gamma-induced gene expression remains unclear.
  • CD40 is a crucial immune system protein, with IFN-gamma identified as a potent inducer of its expression in macrophages and microglia.

Purpose of the Study:

  • To elucidate the molecular mechanisms by which IL-4 inhibits IFN-gamma-induced CD40 expression.
  • To investigate the role of STAT-6 in mediating IL-4's suppressive effects on CD40 gene expression.

Main Methods:

  • Nuclear run-on assays and transfection studies to assess transcriptional regulation.
  • Site-directed mutagenesis of the CD40 promoter to identify key regulatory elements.
  • Electrophoretic Mobility Shift Assays (EMSAs) to determine protein-DNA interactions.

Main Results:

  • IL-4 suppresses IFN-gamma-induced CD40 gene expression transcriptionally in macrophages and microglia, dependent on STAT-6 activation.
  • IL-4's inhibitory effect is specific to CD40, not affecting IFN-gamma-induced IFN-responsive factor-1 gene expression.
  • STAT-6 directly binds to two specific STAT binding sites (proximal and distal IFN-gamma-activated sequences) in the CD40 promoter, mediating IL-4's inhibition.

Conclusions:

  • IL-4 inhibits IFN-gamma-induced CD40 gene expression at the transcriptional level.
  • Direct binding of IL-4-activated STAT-6 to the CD40 promoter is the mechanism underlying this inhibition.
  • This finding provides critical insight into cytokine-mediated immune regulation and gene expression control.

More Related Videos

Highly Efficient Transfection of Human THP-1 Macrophages by Nucleofection07:54

Highly Efficient Transfection of Human THP-1 Macrophages by Nucleofection

Published on: September 2, 2014

Isolation Protocol of Mouse Monocyte-derived Dendritic Cells and Their Subsequent In Vitro Activation with Tumor Immune Complexes11:48

Isolation Protocol of Mouse Monocyte-derived Dendritic Cells and Their Subsequent In Vitro Activation with Tumor Immune Complexes

Published on: May 31, 2018

Related Concept Videos

The JAK-STAT Signaling Pathway01:20

The JAK-STAT Signaling Pathway

Several cytokine receptors have tightly bound Janus kinase or JAK proteins attached at their cytosolic tail. Small signaling molecules such as cytokines, growth hormones, or prolactins bind to the cytokine receptors and initiate their dimerization. The dimerization brings the cytosolic JAKs together that trans-phosphorylate and activates each other. The activated JAKs now phosphorylate cytosolic tails of the cytokine receptors, which serve as binding sites for adaptor proteins such as  SH2...
TGF - β Signaling Pathway01:16

TGF - β Signaling Pathway

The TGF-β signaling pathway regulates cell growth, differentiation, adhesion, motility, and development. TGF-β ligands that induce TGF-β signaling are synthesized in their latent form. Several proteases or cell surface receptors such as integrins act upon the latent form, releasing the active ligand. There are three types of mammalian TGF-βs: (TGF-β1, TGF-β2, and TGF-β3) that bind as homodimers or heterodimers to TGF-β receptors. The TGF-β receptors are of three kinds RI, RII, and RIII. The RI...
T Cell Types and Functions01:24

T 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...