Test Catalog

Test ID: DBS1    
Diabetes Mellitus Type 1 Evaluation, Serum

Method Description Describes how the test is performed and provides a method-specific reference

Immunoprecipitation assays:

(125)I-labeled recombinant human antigen (glutamic acid decarboxylase 65, islet antigen 2, insulin) is added to the test serum. If antibody is present, it forms a soluble complex with the (125)I-labeled antigen. Subsequent addition of goat-antihuman IgG and IgM precipitates the complex. The amount of radioactivity in the precipitate is proportional to the level of antibody in the serum.(Masuda M, Powell M, Chen S, et al: Autoantibodies to IA-2 in insulin-dependent diabetes mellitus. Measurements with a new immunoprecipitation assay. Clin Chim Acta 2000;291:53-66)



ZnT8 antibodies are principally directed against the C terminal domain of ZnT8. The ZnT8 autoantibody ELISA is based on the bridging principle that employs the ability of divalent ZnT8 autoantibodies to bind to ZnT8 coated on to the plate well with one arm, and to liquid ZnT8-biotin with the other arm. Calibrators or undiluted serum samples in duplicate are added to ZnT8 coated plate wells and incubated overnight. ZnT8-biotin is added to each well and plates. After further incubation, aspiration and wash, streptavidin-peroxidase is added to each well. After further incubation, aspiration and wash, peroxidase substrate is added. After further incubation, 0.5 mol/L H2S04 stop solution is added to each well. Absorbance is measured at 450nm, blanked against wells containing peroxidase substrate and H2S04 only (Petruzelkova L, Ananieva-Jordanova R, Vcelakova J, et al: The dynamic changes of zinc transporter 8 autoantibodies in Czech children from the onset of Type 1 diabetes mellitus. Diabet Med 2014;31:165-171).

PDF Report Indicates whether the report includes an additional document with charts, images or other enriched information


Day(s) Performed Outlines the days the test is performed. This field reflects the day that the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time before the test is performed. Some tests are listed as continuously performed, which means that assays are performed multiple times during the day.

GAD65 antibody: Monday through Friday

Insulin antibodies: Monday, Wednesday, Friday

IA-2 antibody, Zinc Transporter 8 Antibody: Tuesday, Thursday

Report Available The interval of time (receipt of sample at Mayo Clinic Laboratories to results available) taking into account standard setup days and weekends. The first day is the time that it typically takes for a result to be available. The last day is the time it might take, accounting for any necessary repeated testing.

7 to 10 days

Specimen Retention Time Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded

28 days

Performing Laboratory Location Indicates the location of the laboratory that performs the test