Glutamic Acid Decarboxylase (Anti-GAD) ELISA Kit

  • Created on the 9 February, 2017.


Human anti-GAD ELISA kit is a reliable quantitative procedure for measuring glutamic acid decarboxylase (GAD) in human serum. This assay has a minimum sensitivity detection limit of 0.57 U/ml.


Glutamic acid decarboxylase (GAD) is an essential marker which has been used to serve for the development of autoimmune diabetes present in adults. This has been useful in helping to identify whether an individual has either latent autoimmune diabetes of adulthood (LADA) or type 1 diabetes. It is well known that the onset of autoimmune diabetes is strongly linked with the presence of autoantibody markers, for diagnostic purpose then anti-GAD is the most common. This antibody is found to be present in over 80% of patients that have type 1 diabetes which has developed during childhood or adolescence.
It is been discovered that anti-GAD and many other antibodies which are directed against pancreatic antigens can be detected for many prior to the clinical onset of autoimmune-mediated diabetes, this provides a clear indication that there must be a long “pre-diabetic” phase which is associated with the autoimmune activity. Other antigens which can also be recognised by anti-GAD include glutamic acid decarboxylase (GAD 65kDa isoform), insulin, islet cell antigen IA-2 and ICA-512.


Reagents which are supplied with the anti-GAD ELISA kit, please following instructions for storage conditions.

1. GAD65 Coated Wells: 12 break-apart strips of 8 wells (96 in total) in a frame and sealed in a foil bag.
2. Calibrators 1-6:  5, 18, 35, 120, 250, 2000 u/mL (units are NIBSC 97/550).
3. Positive Control (see QC datasheet for concentration range).
4. Negative Control.
5. GAD65-Biotin 3 vials, lyophilised.
6. Reconstitution Buffer for GAD65-Biotin.
7. Streptavidin Peroxidase (SA-POD).
8. Diluent for SA-POD.
9. Peroxidase Substrate (TMB).
10. Concentrated Wash Solution.
11. Stop Solution.


The minimum sensitivity detection limit of glutamic acid decarboxylase (GAD) using this human anti-GAD ELISA kit was approximately 0.57 U/ml. The dynamic range for this assay is 5.0 – 2000.0 U/ml.


  1. Immunology of stiff person syndrome and other GAD-associated neurological disorders. Expert Rev Clin Immunol. (2013) 9 (11): 1043-53. Review. Alexopoulos H. and Dalakas M.C.
  2. Spectrum of neurological syndromes associated with glutamic acid decarboxylase antibodies: diagnostic clues for this association. Brain. (2008) 131 (Pt 10): 2553-2563. Saiz et al.
  3. The broad clinical phenotype of Type 1 diabetes at presentation. Diabet Med. (2013) 30 (2): 170-8. Merger et al.
  4. Expression of recombinant human glutamic acid decarboxylase (GAD) in myeloma cells and enzyme-linked immunosorbent assay (ELISA) for autoantibodies to GAD. J Biochem. (1997) 121 (1): 20-4. Matsuba T., et al.


  • Full Name: Glutamic Acid Decarboxylase (Anti-GAD) ELISA Kit
  • Reactivity: Human
  • Sample Type: Serum
  • Sensitivity: 0.57 U/ml



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