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Updated: Apr 27, 2026

In Situ Detection of Autoreactive CD4 T Cells in Brain and Heart Using Major Histocompatibility Complex Class II Dextramers
Published on: August 1, 2014
In vivo analysis of helper T cell responses in patients with autoimmune polyendocrinopathy - candidiasis - ectodermal
Sini M Laakso1, Eliisa Kekäläinen, Nelli Heikkilä
1Department of Immunology, Haartman Institute, and Research Programs Unit, Immunobiology, University of Helsinki , Helsinki , Finland .
Abstract:
Autoimmune polyendocrinopathy - candidiasis - ectodermal dystrophy (APECED) is caused by mutations in the Autoimmune regulator (AIRE) gene and is associated with neutralizing anti-cytokine autoantibodies. We have used an in vivo challenge model to analyze antigen-specific CD4(+) T cell responses. Bacille Calmette-Guérin (BCG)-vaccinated patients and controls were injected tuberculin intradermally, skin blisters were induced by suction on the indurations and on unexposed skin, and the infiltrating cells harvested. The patients had a quantitatively normal CD4(+) T cell response and no significant abnormalities in the expression of T helper type (Th) 1- or Th2-related genes. The expression of interleukin (IL)-22, in contrast, was lower in the patients. Two patients, both with a pre-existing ocular keratopathy, experienced a relapse of keratoconjunctivitis, suggesting a possible immunological basis for this APECED component. Our in vivo data are compatible with a selective IL-22 defect in the activated CD4(+) T cells of APECED patients, affecting also unexposed skin in steady-state conditions.

