Increased intraepithelial Vα24 invariant NKT cells in the celiac duodenum

Celiac Disease (CD) is an interferon (IFN)γ-mediated duodenal hypersensitivity to wheat gluten occurring in genetically predisposed individuals. Gluten-free diet (GFD) leads to a complete remission of the disease. Vα24-restricted invariant NKT (iNKT) cells are important to maintain immune homeostasis in the gut mucosa because of their unique capacity to rapidly produce large quantities of both T-helper (Th)1 and Th2 cytokines upon stimulation. We studied the presence of these cells in the CD duodenum. Duodenal biopsies were obtained from 45 untreated-CD patients (uCD), 15 Gluten Free Diet-CD patients (GFD-CD), 44 non-inflamed non-CD controls (C-controls) and 15 inflamed non-CD controls (I-controls). Two populations from Spain and Argentina were recruited. Messenger RNA (mRNA) expression of Vα24-Jα18 (invariant TCRα chain of human iNKT cells), IFNγ and intracellular transcription factor Forkhead Box P3 (Foxp3), and flow cytometry intraepithelial lymphocyte (IEL) profile were determined. Both uCD and GFD-CD patients had higher Vα24-Jα18 mRNA levels than non-CD controls (I and C-controls). The expression of Vα24-Jα18 correlated with Marsh score for the severity of mucosal lesion and also with increased mRNA IFNγ levels. uCD and GFD-CD patients had decreased mRNA expression of FoxP3 but increased expression of Vα24-Jα18, which revealed a CD-like molecular profile. Increased numbers of iNKT cells were confirmed by flow cytometry within the intraepithelial lymphocyte compartment of uCD and GFD-CD patients and correlated with Vα24-Jα18 mRNA expression. In conclusion, we have found an increased number of iNKT cells in the duodenum from both uCD and GFD-CD patients, irrespective of the mucosal status. A CD-like molecular profile, defined by an increased mRNA expression of Vα24-Jα18 together with a decreased expression of FoxP3, may represent a pro-inflammatory signature of the CD duodenum.Fil: Montalvillo, Enrique. Universidad de Valladolid; España. Consejo Superior de Investigaciones Científicas; EspañaFil: Bernardo, David. Imperial College London; Reino Unido. Hospital Universitario de La Princesa ; Países BajosFil: Martínez Abad, Beatriz. Universidad de Valladolid; España. Consejo Superior de Investigaciones Científicas; España. Instituto de Investigación Sanitaria Princesa; EspañaFil: Allegretti, Yessica Lorena. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Ciencias Biológicas. Laboratorio de Investigaciones del Sistema Inmune; ArgentinaFil: Fernández Salazar, Luis. Hospital Clínico Universitario; EspañaFil: Calvo, Carmen. Hospital Clínico Universitario; EspañaFil: Chirdo, Fernando Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Ciencias Biológicas. Laboratorio de Investigaciones del Sistema Inmune; ArgentinaFil: Garrote, José A.. Universidad de Valladolid; España. Consejo Superior de Investigaciones Científicas; España. Hospital Universitario Rio Hortega; EspañaFil: Arranz, Eduardo. Universidad de Valladolid; España. Consejo Superior de Investigaciones Científicas; Españ