Poster Presentation The 13th International Congress of the Immunology of Diabetes Society 2013

T-cell autoreactivity at onset of pediatric Type 1 Diabetes (T1D) is related to adiposity but not autoantibodies nor c-peptide (#66)

Melissa Buryk 1 , H-Michael Dosch 2 , Ingrid Libman 1 , Roy K Cheung 2 , Vincent Arena 3 , Yihe Huang 4 , Massimo Trucco 1 , Massimo Pietropaolo 5 , Dorothy J Becker 1
  1. Children's Hospital of Pittsburgh, Pittsburgh, PA, United States
  2. Hospital for Sick Children, Toronto, ON, Canada
  3. School of Public Health, University of Pittsburgh, Pittsburgh, PA, United States
  4. School of Public Health, University of Pittsburgh, Pittsburgh, PA, United States
  5. Department of Immunology, University of Michigan, Ann Arbor, MI, United States

Objectives:T-cell reactivity to diabetes-related antigens distinguishes T1D from controls and may precede autoantibody (Ab) detection. Relationships between adiposity and T-cell reactivity in T1D are unknown. We assessed relationships between T-cell reactivity to T1D-related antigens and islet autoantibodies, measures of adiposity and insulin sensitivity and c-peptide in normal and overweight new onset T1D children.

Methods:Subjects with T1D between 12/2004 and 6/2008 were included (n=261): age 1.2-18.9yrs, 92% white, 60% male. T-cell autoreactivity to 10 antigens, Ab (GADA, IA-2A, IAA, ICA), body mass index (BMI) %ile, waist %ile and c-peptide at onset and 3 months were measured.

Results:Abnormal T cell reactivities were not related to autoantibody number, nor HLA.DQ. Subjects with BMI %ile ≥85th had higher T-cell autoreactivities to 5 neuronal T1D-associated analytes (p< 0.05). Subjects with waist %ile ≥85th had higher SI’s for 3 neuronal analytes, (p<0.05). The 28 Ab negative subjects (only 1 also T-cell negative) had similar c-peptides, but higher BMIz than those with positive Ab. The cohort was subdivided by Ab and T-cell characteristics. (table 1)

Conclusions:This observation links elevated BMI and T-cell autoreactivity in T1D. In overweight new onset T1D children, T-cell autoreactivity to neuronal analytes is enhanced by adiposity and insulin resistance. With 1 exception, the entire cohort demonstrated islet autoimmunity with similarly low c-peptide levels.