Key Features and Values
– Wide variety of sample types to simplify inclusion into routine serology work-up
– No observed matrix effect in paediatric samples excludes pre-treatment steps
– Ready to use reagents reduces hands-on time for assay preparation
– Long shelf life cost-effective solution by reducing wastage due to expired kits
– Suitable for inclusion on automated plate systems simplifies scale-up of test volume
Anti Deamidated Gliadin Peptide (DPG) IgA kit is a solid phase enzyme immunometric assay (ELISA) designed for the quantitative measurement of IgA class antibodies directed against deamidated Gliadin peptides (DGP) in human serum or plasma. Anti Deamidated Gliadin Peptide (DPG) IgA is intended for laboratory use only.
It has been demonstrated that coeliac subjects synthesise specific antibodies against the agent Gliadin, known as Deamidated Gliadin Peptides (DGP). Anti-DGP antibodies are highly specific markers for identifying gluten-intolerant subjects, differently from the anti-gliadin antibodies, which are also found in healthy subjects or in subjects affected by other enteric disorders and are therefore less specific6. The latest generation of assays therefore involve the detection of these anti- DGP antibodies. These assays have been found to perform comparatively well against anti-TG tests7 and assays detecting anti-DGP IgG have been found to be highly accurate in patients with IgA deficiency.
In paediatric populations there is some indication that anti-DGP assays may provide further uses as these assays have a very high level of diagnostic accuracy in both high and low risk populations7-8. Several studies investigating the assessment of DGP antibody levels in paediatric populations (children under the age of 2 years) have demonstrated 100% diagnostic accuracy of this marker9-10 even in cases where normal levels of TG have been determined9.
There is an observed inverse association between anti-DGP IgA and IgG, and age at diagnosis, with children aged 7 years and under showing significantly higher values than older patients11. Furthermore, it has been found that anti-DGP antibodies precede the appearance of TG antibodies in some children with genetic risk for CD11. This gives rise to the possibility of using anti-DGP IgA / IgG assays as an earlier indicator for CD in certain infant populations. A further study in infants found that levels of DGP antibodies correlated with the severity of intestinal damage12. Use of the test for anti-DGP IgA and IgG antibodies is also recommended in all subjects, regardless of age, showing symptoms suggestive of CD and in whom the t-TG or EMA autoantibodies are absent or present only at low titres13.
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7. Sugai E, Vazquez H, Nachman F, et al. Accuracy of testing for antibodies to synthetic gliadin-related peptides in celiac disease. Clin Gastroenterol Hepatol. 2006;4:1112–7
9. Barbato M, Maiella G, Di Camillo C, et al. The anti-deamidated gliadin peptide antibodies unmask celiac disease in small children with chronic diarrhoea. Dig Liver Dis. 2011;43:465–9
10. Mubarak A, Gmelig-Meyling FH, Wolters VM, Ten Kate FJ, Houwen RH. Immunoglobulin G antibodies against deamidated-gliadin-peptides outperform anti-endomysium and tissue transglutaminase antibodies in children <2 years age. APMIS. 2011;119:894–900
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12. Amarri S, Alvisi P, De Giorgio R, Gelli MC, Cicola R, Tovoli F, Sassatelli R, Caio G, Volta U. Antibodies to Deamidated Gliadin Peptides: An Accurate Predictor of Coeliac Disease in Infancy. J Clin Immunol (2013) 33:1027–1030
13. Tonutti E, Visentini D, Picierno A, Bizzarro N, Villalta D, Bozzoli R, et al. Diagnostic efficacy of the ELISA tests for the detection of deamidated anti gliadin antibodies in the diagnosis and monitoring of celiac disease. J Clin Lab Anal. 2009; 23(3): 172-4