Size and dynamics of mucosal and peripheral IL-17A+ T-cell pools in pediatric age, and their disturbance in celiac disease

Mucosal Immunol. 2012 Sep;5(5):513-23. doi: 10.1038/mi.2012.26. Epub 2012 May 9.

Abstract

Mucosal interleukin (IL)-17A-producing T cells contribute to protective antimicrobial responses and to epithelial barrier integrity; their role in celiac disease (CD) is debated. We analyzed the frequency and developmental dynamics of mucosal (intraepithelial lymphocytes (IEL)) and circulating (peripheral blood (PB)) IL-17A (T17) and/or interferon (IFN)-γ-producing (T1, T1/T17) T-cell populations in 86 pediatric controls and 116 age-matched CD patients upon phorbol myristate acetate/ionomycin or CD3/CD28 stimulation. T17 and T1/17 are physiologically present among IEL and PB populations, and their frequency is selectively and significantly reduced in CD IEL. The physiological age-dependent increase of Th17 IEL is also absent in CD, while IFN-γ-producing PB-T cells significantly accumulate with patient's age. Finally, the amplitude of IL-17A+ and IFN-γ+ T-cell pools are significantly correlated in different individuals; this relationship only applies to CD4+ T cells in controls, while it involves also the CD4- counterpart in CD patients. In conclusion, both size and dynamics of mucosa-associated and circulating IL-17A+ T-cell pools are finely regulated in human pediatric subjects, and severely disturbed in CD. The impaired IL-17A+ IEL-T pool may negatively impact on epithelial barrier efficiency, and contribute to CD mucosa damage; the disturbed dynamics of circulating IL-17A+ and IFN-γ+ T-cell pools may be involved in the extraintestinal autoimmune manifestations associated with CD.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Blood Circulation / immunology
  • CD4-Positive T-Lymphocytes / immunology
  • Celiac Disease / immunology*
  • Cell Proliferation
  • Child
  • Duodenum / immunology*
  • Humans
  • Immunity, Mucosal
  • Immunophenotyping
  • Interferon-gamma / metabolism
  • Interleukin-17 / metabolism*
  • Lymphocyte Activation
  • Lymphocyte Count
  • T-Lymphocyte Subsets / immunology*
  • Th17 Cells / immunology*

Substances

  • Interleukin-17
  • Interferon-gamma