ICA and organ-specific autoantibodies among Japanese patients with early-onset insulin-dependent diabetes mellitus--the JDS study.

The Japan Diabetes Society (JDS) conducted a multicenter study on the immunogenetics of insulin-dependent diabetes mellitus (IDDM) among Japanese. The previous report of the JDS study described HLA types and other immunogenetic markers in Japanese patients with IDDM. In the present report, the autoimmunity of Japanese patients was studied by measuring ICA and other organ-specific autoantibodies in patients with different durations of IDDM. The prevalences of ICA were the highest in the first year after diagnosis (73.1%) and decreased to 58.0%, 18.3% and 2.8% in 1-5 years, 5-10 years and 10 years or more after diagnosis, respectively (P < 0.01), while the prevalences of the other organ specific autoantibodies increased gradually with duration of IDDM from 20% in the first year to 35% in 10 years or more after diagnosis (P < 0.05). There were no sex differences in the prevalences of ICA but those of other organ-specific autoantibodies were significantly higher in female patients than in male patients (P < 0.01). The prevalence of ICA was not correlated with sex, age at onset or HLA types. In one of the subjects, a girl, the titers of ICA increased in parallel with a decrease in insulin secretion before the development of overt IDDM and declined thereafter. These findings suggest that IDDM might develop when the autoimmunity specific to pancreatic islets is triggered in people with underlying autoimmunity as shown by the presence of organ-specific autoantibodies other than ICA.

Immunogenetics of early-onset insulin-dependent diabetes mellitus among the Japanese: HLA, Gm, BF, GLO, and organ-specific autoantibodies--the J.D.S. study.

The Japan Diabetes Society (JDS) conducted a multicenter study on the immunogenetics of early-onset insulin-dependent diabetes mellitus (IDDM) of the Japanese. Human leukocyte antigen (HLA), properdin factor B (BF), immunoglobulin heavy-chain complex (Gm), and glyoxalase of erythrocytes (GLO) were typed, and organ-specific autoantibodies, including islet cell antibody (ICA), were assayed in 159 Japanese IDDM patients and their family members and in 258 healthy Japanese controls. The HLA-DRw9 phenotype and HLA-Bw61/DRw9 haplotype were significantly increased among the patients with autoantibodies other than ICA but with no autoimmune diseases (RR = 5.84, cP less than 0.001; and RR = 7.45, P less than 0.001), whereas the HLA-DR4 phenotype and HLA-Bw54/DR4 haplotype were significantly increased in those without either the autoantibodies or autoimmune diseases (RR = 2.64, cP less than 0.001; and RR = 4.55, P less than 0.001). The HLA-DR4 phenotype was significantly increased in the patients with autoimmune thyroid diseases (RR = 6.21, cP less than 0.05). In all groups of patients, the HLA-DR2 phenotype was significantly decreased, and the relative risk of the HLA-DRw9/DR4 genotype was highest among all HLA-DR genotypes. No significant association was found between HLA type and the duration or incidence of ICA. Gm types of g and gft were significantly increased in the patients with the autoantibodies (RR = 2.11, P less than 0.05; and RR = 34.11, P less than 0.05), whereas the BF-F phenotype was significantly decreased in the patients either with or without autoantibodies (RR = 0.43, P less than 0.05; and RR = 0.46, P less than 0.05). There was no association between IDDM and GLO type. These data indicate that immunogenetic bases underlying IDDM of the Japanese are heterogeneous, as are those in Caucasians.