Profound Reduction in T-helper (Th) 1 lymphocytes in Peripheral Blood from Patients with Concurrent Type 1 Diabetes and Graves' Disease

• Published in: ENDOCRINE JOURNAL Vol. 53; no. 3; pp. 377 - 385
• Main Authors: YOSHIMASA ASO, HIROMI MATSUURA, ATSUSHI MOMOBAYASHI, YOSHIHISA INUKAI, NAOTO SUGAWARA, TOMOKI NAKANO, RURIKO YAMAMOTO, SADAO WAKABAYASHI, KOHZO TAKEBAYASHI, TOSHIHIKO INUKAI
• Format: Journal Article
• Language: Japanese
• Published: The Japan Endocrine Society 2006
• ISSN: 0918-8959

Type 1 diabetes likely is mediated by T-helper (Th) 1 lymphocytes, while Graves' disease may involve Th2 predominance. We investigated the balance between Th1 and Th2 cells and between Th1- and Th2-associated chemokine receptor expression on peripheral lymphocytes in subjects including patients with coexisting type I diabetes and Graves' disease. Peripheral blood mononuclear cells of all subjects were examined by flow cytometry for intracellular cytokines (IFN-γ for Th1；IL-4 for Th2) and expression of the chemokine receptors CXCR3 (Th1-associated) and CCR4 (Th2-associated). Plasma concentrations of interferon-inducible protein (IP)-10, a CXCR3 ligand, and thymus and activation-regulated chemokine (TARC), a CCR4 ligand, were measured by enzyme-linked immunosorbent assays. IFN-γ producing-T lymphocytes were significantly fewer in patients with coexisting type 1 diabetes and Graves' disease (12.4 ± 6.8%, n=6) than in healthy control subjects (19.9 ± 4.1%, n=6；P<0.01) or patients with type 2 diabetes (19.1 ± 4.5%, n=5；P<0.05). We found no significant difference in IFN-γ-producing T lymphocytes between healthy controls and patients with only type 1 diabetes (n=8) or Graves' disease (n=5). Plasma IP-10 concentrations were significantly higher in patients with coexisting type 1 diabetes and Graves' disease than in control subjects (106.3 ± 30.48 vs. 66.7 ± 25.3 pg/ml. P=0.0343). Considering only patients with type 1 diabetes alone, duration of diabetes correlated positively with IFN-γ-producing T lymphocytes (r=0.773, P=0.0242) and the ratio of CXCR3 to CCR4 receptor expression (r=0.947, P=0.0004). In conclusion, Th1-associated T lymphocytes were fewer in peripheral blood from patients having both type 1 diabetes and Graves' disease than in those with either disease alone. Numbers of peripheral Th1 lymphocytes increased with increasing time from onset of type 1 diabetes in patients with type 1 diabetes alone.