High levels of type 2 cytokine-producing cells in chronic fatigue syndrome

Clin Exp Immunol. 2004 Feb;135(2):294-302. doi: 10.1111/j.1365-2249.2004.02354.x.


The aetiology of chronic fatigue syndrome (CFS) is not known. However, it has been suggested that CFS may be associated with underlying immune activation resulting in a Th2-type response. We measured intracellular production of interferon (IFN)-gamma and interleukin (IL)-2; type 1 cytokines), IL-4 (type 2) and IL-10 (regulatory) by both polyclonally stimulated and non-stimulated CD4 and CD8 lymphocytes from patients with CFS and control subjects by flow cytometry. After polyclonal activation we found evidence of a significant bias towards Th2- and Tc2-type immune responses in CFS compared to controls. In contrast, levels of IFN-gamma, IL-2 and IL-10-producing cells were similar in both study groups. Non-stimulated cultures revealed significantly higher levels of T cells producing IFN-gamma or IL-4 in CFS patients. Concluding, we show evidence for an effector memory cell bias towards type 2 responsiveness in patients with CFS, as well as ongoing type 0 immune activation in unstimulated cultures of peripheral blood cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • CD4-Positive T-Lymphocytes / immunology
  • CD8-Positive T-Lymphocytes / immunology
  • Cells, Cultured
  • Cytokines / biosynthesis*
  • Fatigue Syndrome, Chronic / blood
  • Fatigue Syndrome, Chronic / immunology*
  • Female
  • Flow Cytometry / methods
  • Humans
  • Immunoglobulin E / blood
  • Interferon-gamma / biosynthesis
  • Interleukins / biosynthesis
  • Male
  • Middle Aged
  • T-Lymphocytes / immunology*
  • T-Lymphocytes, Cytotoxic / immunology
  • Th2 Cells / immunology*


  • Cytokines
  • Interleukins
  • Immunoglobulin E
  • Interferon-gamma