Anti-tissue Transglutaminase Enzyme-Linked Immunosorbent Assay for Screening of Celiac Disease in Moroccan Pediatric Patients

Abstract

Celiac disease (CD) is an immune-mediated systemic disorder elicited by gluten which induces an enteropathy with atrophy of intestinal villi. No prevalence information was available for CD in Moroccan children because the diagnosis is based on multiple invasive duodenal biopsies. To simplify CD diagnosis, the objective of this work was to develop an Enzyme-linked Immunosorbent Assay (ELISA) for IgA and IgG tissue transglutaminase (tTG) antibodies detection suitable for Moroccan children. The concentration of the coated antigen and serum dilutions were optimized for the development of IgA anti- tTG and IgG anti-tTG ELISA detection in serum. The cut-off was calculated and the developed ELISAs were used for detecting IgA and IgG-tTG antibodies in 97 serum samples from 97 children aged 1 to 13 years, with variable clinical characteristics. After adjusting optimal working conditions of ELISA, the cut-offs were 0.04 and 0.156 AU for detecting anti-tTG and IgA anti-tTG IgG respectively. The use of IgG anti-tTG as CD marker (100 % of sensitivity) was better than the use of IgA anti-tTG in ELISA tests (90.3% sensitivity). In addition, the ELISA test shows a clear correlation between the IgG tTG antibodies titer and the degree of duodenal damage, estimated by the Marsh stages classification in patients with confirmed CD. Our results suggest that the assessment of the adapted IgG anti-tTG ELISA test can be used for CD in initial screening in Moroccan children after validation with a larger number of samples with CD for confirmation.