Zinc transporter 8 antibodies complement GAD and IA-2 antibodies in the identification and characterization of adult-onset autoimmune diabetes: Non Insulin Requiring Autoimmune Diabetes (NIRAD) 4
- PMID: 19808923
- PMCID: PMC2797953
- DOI: 10.2337/dc08-2305
Zinc transporter 8 antibodies complement GAD and IA-2 antibodies in the identification and characterization of adult-onset autoimmune diabetes: Non Insulin Requiring Autoimmune Diabetes (NIRAD) 4
Abstract
Objective: Zinc transporter 8 (ZnT8) is an islet beta-cell secretory granule membrane protein recently identified as an autoantibody antigen in type 1 diabetes. The aim of this study was to determine the prevalence and role of antibodies to ZnT8 (ZnT8As) in adult-onset diabetes.
Research design and methods: ZnT8As were measured by a radioimmunoprecipitation assay using recombinant ZnT8 COOH-terminal or NH(2)-terminal proteins in 193 patients with adult-onset autoimmune diabetes having antibodies to either GAD (GADAs) or IA-2 (IA-2As) and in 1,056 antibody-negative patients with type 2 diabetes from the Non Insulin Requiring Autoimmune Diabetes (NIRAD) study.
Results: ZnT8As-COOH were detected in 18.6% patients with autoimmune diabetes and 1.4% with type 2 diabetes. ZnT8As-NH(2) were rare. ZnT8As were associated with younger age and a high GADA titer. The use of GADAs, IA-2As, and ZnT8As in combination allowed a stratification of clinical phenotype, with younger age of onset of diabetes and characteristics of more severe insulin deficiency (higher fasting glucose and A1C, lower BMI, total cholesterol, and triglycerides) in patients with all three markers, with progressive attenuation in patients with two, one, and no antibodies (all P(trend) < 0.001). Autoantibody titers, association with high-risk HLA genotypes, and prevalence of thyroid peroxidase antibodies followed the same trend (all P < 0.001).
Conclusions: ZnT8As are detectable in a proportion of patients with adult-onset autoimmune diabetes and seem to be a valuable marker to differentiate clinical phenotypes.
Figures


References
-
- Palmer JP, Asplin CM, Clemons P, Lyen K, Tatpati O, Raghu PK, Paquette TL: Insulin antibodies in insulin-dependent diabetics before insulin treatment. Science 1983; 222: 1337– 1339 - PubMed
-
- Baekkeskov S, Aanstoot HJ, Christgau S, Reetz A, Solimena M, Cascalho M, Folli F, Richter-Olesen H, De Camilli P, Camilli PD: Identification of the 64K autoantigen in insulin-dependent diabetes as the GABA-synthesizing enzyme glutamic acid decarboxylase. Nature 1990; 347: 151– 156 - PubMed
-
- Bonifacio E, Lampasona V, Genovese S, Ferrari M, Bosi E: Identification of protein tyrosine phosphatase-like IA2 (islet cell antigen 512) as the insulin-dependent diabetes-related 37/40K autoantigen and a target of islet-cell antibodies. J Immunol 1995; 155: 5419– 5426 - PubMed
-
- Turner R, Stratton I, Horton V, Manley S, Zimmet P, Mackay IR, Shattock M, Bottazzo GF, Holman R: UKPDS 25: autoantibodies to islet-cell cytoplasm and glutamic acid decarboxylase for prediction of insulin requirement in type 2 diabetes. UK Prospective Diabetes Study Group. Lancet 1997; 350: 1288– 1293 - PubMed
Publication types
MeSH terms
Substances
LinkOut - more resources
Full Text Sources
Medical
Research Materials