Activated gut-homing CD8+ T cells for coeliac disease diagnosis on a gluten-free diet

Abstract

Background The diagnosis of coeliac disease (CD) in individuals that have started a gluten-free diet (GFD) without an adequate previous diagnostic work-out is a challenge. Several immunological assays such as IFN-γ ELISPOT have been developed to avoid the need of prolonged gluten challenge to induce the intestinal damage. We aimed to evaluate the diagnostic accuracy of activated gut-homing CD8+ and TCRγδ+ T cells in blood after a 3-day gluten challenge and to compare it with the performance of IFN-γ ELISPOT in a HLA-DQ2.5 subsample. Methods A total of 22 CD patients and 48 non-CD subjects, all of them following a GFD, underwent a 3-day 10-g gluten challenge. The percentage of two T cell subsets (CD8+ CD103+ β7hi CD38+/total CD8+ and TCRγδ+ CD103+ β7hi CD38+/total TCRγδ+) in fresh peripheral blood drawn baseline and 6 days after the challenge was determined by flow cytometry. IFN-γ ELISPOT assays were also performed in HLA-DQ2.5 participants. ROC curve analysis was used to assess the diagnostic performance of the CD8+ T cell response and IFN-γ ELISPOT. Results Significant differences between the percentage of the two studied subsets of CD8+ and TCRγδ+ cells at days 0 and 6 were found only when considering CD patients (p < 10−3 vs. non-CD subjects). Measuring activated CD8+ T cells provided accurate CD diagnosis with 95% specificity and 97% sensitivity, offering similar results than IFN-γ ELISPOT. Conclusions The results provide a highly accurate blood test for CD diagnosis in patients on a GFD of easy implementation in daily clinical practice.

Intestinal and blood lymphograms as new diagnostic tests for celiac disease

“…The findings of Han et al. ( 6 ) were used by our research group to try a new test to diagnose CD and thus we showed that the study of activated gut-homing CD8 + T cells by flow cytometry offered 95% specificity and 97% sensitivity for detecting seropositive CD ( 39 ). This test has a presumed easy implementation in clinical practice.…”

“…The authors concluded that the celiac lymphogram was associated with a high level of diagnostic evidence either against or in favor of CD in patients with SNVA. The celiac lymphogram has also been shown to be a useful tool to consider Marsh 1 lesions as CD ( 29 , 31 , 32 , 39 – 41 ). Using dermatitis herpetiformis as a model disease in which there are gluten-related symptoms despite of a non-atrophic enteropathy, even with negative celiac serology in a high percentage of patients, Popp and Mäki argue about the existence of a ‘celiac trait’, consisting in a Marsh 1 lesion, positive celiac genetics and increase in γδ + cells, that should be identified and treated since they present clinical and histological remission after a GFD ( 42 ).…”

“…Therefore, it is crucial to compare the percentage of the studied lymphocytes before and after gluten intake. Other potential limitation, shared with the others methodological approaches based on the activation of memory T cells, is that a lack of response to the gluten challenge may exist in patients with more than 18 years in a GFD ( 39 , 60 ). However, a second challenge at least 3 months later most probably gives a positive result in CD patients ( 60 ).…”