Human anti-DGP IgA ELISA kit can be used for measuring in vitro quantitative amounts of IgA-antibodies directed against anti deamidated gliadin protein epitopes (anti-DGP IgA) in human plasma and serum samples. This assay has a minimum analytical sensitivity limit of 1.0 U/ml.
Anti deamidated gliadin antibodies can be used for diagnosing celiac disease and many other related conditions that are sensitive to gluten for example dermatitis herpetiformis. Celiac disease is an example of an autoimmune disorder where the body’s immune system mistakenly thinks that gluten (a protein in wheat, oats, rye and barley) is a foreign invader. Gliadin is a portion of the protein that is present in gluten and the immune system produces anti gliadin antibodies (AGA) in order to attack the protein. These antibodies can be either immunoglobulin A (IgA) or immunoglobulin G (IgG), IgA is more useful in helping to detect celiac disease since it is produced in the small intestine, a region where gluten causes irritation and inflammation in sensitive people.
One of the main drawbacks for using deamidated gliadin antibodies is that they can also be found in people without celiac disease, therefore this test usually lacks specificity when compared to measuring transglutaminase and endomysium levels. However, recent research has discovered that gliadin reactive antibodies from celiac patients have the ability to bind a limited number of specific epitopes that are present on the gliadin molecule. The use of deamidated gliadin peptides (DGP IgA and DGP IgG) provides a means of measuring specific and accurate levels. Deamidated gliadin proteins or peptides have the ability bind to the HLA molecules of antigen-presenting cells. Once they are placed in context with specific HLA molecules, these fragments are recognised by corresponding T-helper cells. This process leads to an extensive immune response resulting in the formation of antibodies against deamidated gliadin protein (DGP) and tissue transglutaminase (tTG).
ANTI-DGP IGA ELISA KIT CONTENT
All reagents supplied need to be stored at 2 °C – 8 °C, unopened reagents will retain reactivity until expiration date. Do not use reagents beyond this date.
- Divisible Microplate: Consisting of 12 modules of 8 wells each, deamidated gliadin proteins are bound to microwells.
- Calibrator A-F: Concentration 0, 6.3, 12.5, 25, 50, 100 U/ml, made up from DGP IgA antibodies in a serum/buffer matrix.
- Control Positive and Control Negative: Containing human anti-DGP IgA.
- Sample Buffer P (5x).
- Enzyme Conjugate: Contains anti-human IgA antibodies, HRP labelled.
- Substrate: Tetramethylbenzidin (TMB).
- Stop Solution.
- Wash Buffer (50x).
- Instruction for Use.
- Certificate of Analysis.
The minimum detection sensitivity level of IgA antibodies to deamidated gliadin protein epitopes (anti-DGP IgA, anti DGP IgA) using current anti-DGP IgA ELISA kit was 1.0 U/ml. The dynamic range for this assay is 6.3 – 100.0 U/ml.
– Anti-Deamidated Gliadin Protein IgA (Anti-DGP IgA): ELISA
– Measuring Range: 0 – 100 U/ml.
– Expected Values: Healthy blood donors display a cut-off 10 U/ml
– Results Interpretation: Negative: < 10 U/ml Positive: ≥ 10 U/ml
– Linearity: 81 – 100%
– Limit Of Detection (LOD): Functional sensitivity is 1 U/ml
– Intra Assay: 4.0 – 6.0%
– Inter Assay: 1.7 – 8.7%
– Interfering Substances: None
– Clinical Diagnosis: Sensitivity (70.0%), Specificity (100.0%), Overall agreement (86.7%).
- Deamidated gliadin peptides as targets for celiac disease-specific antibodies. Adv Clin Chem. (2007) 44: 35-63. Review. Mothes T.
- Digesting all the options: laboratory testing for celiac disease. Crit Rev Clin Lab Sci. (2014) 51 (6): 358-78. Review. Barakauskas V.E., et al.
- Overview of biomarkers for diagnosis and monitoring of celiac disease. Adv Clin Chem. (2015) 68: 1-55. Brusca I.
- Deamidated gliadin peptides form epitopes that transglutaminase antibodies recognize. J Pediatr Gastroenterol Nutr. (2008) 46 (3): 253-61. Korponay-Szabó I.R., et al.
- [Treating coeliac disease. How do we measure adherence to the gluten-free diet?] Rev Chil Pediatr. (2016) 87 (6): 442-448. Review. Aranda E.A. and Araya M.
- Current trends and investigative developments in celiac disease. Immunol Invest. (2013) 42 (4): 273-84. Review. Samaşca G., et al.
- Full Name: Anti-DGP IgA ELISA Kit
- Reactivity: Human
- Sample Type: Plasma, Serum
- Sensitivity: 1.0 U/ml