Related Experiment Video

Updated: Jun 21, 2026

Lymphocyte Isolation from Human Skin for Phenotypic Analysis and Ex Vivo Cell Culture
10:31

Lymphocyte Isolation from Human Skin for Phenotypic Analysis and Ex Vivo Cell Culture

Published on: April 8, 2016

IL-18 skews the invariant NKT-cell population via autoreactive activation in atopic eczema

Sara M Lind1, Carlotta Kuylenstierna, Markus Moll

  • 1Clinical Allergy Research Unit, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden.

European Journal of Immunology
|July 29, 2009
PubMed

Insights

Interleukin-18 (IL-18) activates invariant natural killer T (iNKT) cells in atopic eczema (AE). Chronic IL-18 exposure suppresses CD4(+) iNKT cells, correlating with AE severity and IgE levels.

Area of Science:

  • Immunology
  • Dermatology
  • Microbiology

Background:

  • Atopic eczema (AE) is a chronic inflammatory skin condition.
  • The yeast Malassezia can trigger AE flares.
  • Interleukin-18 (IL-18), an innate cytokine elevated in AE patients, is produced by dendritic cells activated by Malassezia.

Purpose of the Study:

  • To investigate the role of IL-18 in the human invariant NKT (iNKT) cell compartment in AE.
  • To understand how IL-18 affects iNKT cell responses in the context of AE pathogenesis.

Main Methods:

  • Investigated the effect of IL-18 on human iNKT cells in vitro.
  • Analyzed iNKT cell populations (CD4+ vs. CD4-) in peripheral blood of AE patients.
  • Measured plasma levels of IL-18, total IgE, and correlated these with disease severity.

Main Results:

  • IL-18 potently activates human iNKT cells, inducing a pro-inflammatory CD1d-dependent response.
  • Chronic IL-18 exposure inhibits iNKT cells, specifically suppressing CD4+ iNKT cells.
  • AE patients exhibit reduced CD4+ iNKT cell proportions, elevated IL-18 plasma levels, and a correlation between IL-18, IgE, and disease severity.

Conclusions:

  • IL-18 plays a significant role in the pathogenesis of human atopic eczema.
  • Dysregulation of CD1d-restricted iNKT cells by IL-18 contributes to AE development.
  • Targeting IL-18 or modulating iNKT cell responses could be potential therapeutic strategies for AE.

Related Concept Videos

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...
T Cell Activation and Clonal Selection01:22

T 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...