Immune regulatory T cells in siblings of children suffering from type 1 diabetes mellitus

Scand J Immunol. 2006 Nov;64(5):531-5. doi: 10.1111/j.1365-3083.2006.01837.x.

Abstract

Patients with type 1 diabetes are suffering from defects in immune regulatory cells. Their siblings may be at increased risk of type 1 diabetes especially if they are carriers of certain human leucocyte antigen (HLA) alleles. In a prospective non-randomized study, we intended to evaluate 31 healthy siblings of paediatric patients with type 1 diabetes and explore immune regulatory populations of CD4+CD25+ T cells and natural killer (NK) T cells. Tested siblings of type 1 diabetes patients were stratified according to the HLA-associated risk of possible diabetes development. Immune regulatory function of CD4+CD25+ T cells was tested in vitro. Significant differences in CD4+CD25+ but not in NK T cells have been identified. Siblings of type 1 diabetes patients carrying high risk HLA alleles (DQA1*05, DQB1*0201, DQB1*0302) had significantly lower number of immune regulatory CD4+CD25+ T cells than the age-matched healthy controls or siblings carrying low-risk HLA alleles (DQB1*0301, DQB1*0603, DQB1*0602). Regulatory function of CD4+CD25+ T cells demonstrated a dose-escalation effect. In siblings of type 1 diabetes patients, the defect in immune regulatory CD4+CD25+ T cells exists in association with genetic HLA-linked risk for type 1 diabetes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Autoantibodies / immunology
  • CD4-Positive T-Lymphocytes / immunology
  • CD4-Positive T-Lymphocytes / physiology
  • Case-Control Studies
  • Child
  • Child, Preschool
  • Diabetes Mellitus, Type 1 / genetics
  • Diabetes Mellitus, Type 1 / immunology*
  • Female
  • Genetic Predisposition to Disease*
  • HLA Antigens / genetics
  • Humans
  • Infant
  • Killer Cells, Natural / physiology
  • Male
  • Siblings*
  • T-Lymphocytes, Regulatory / immunology*

Substances

  • Autoantibodies
  • HLA Antigens