T-cell response to different cultivars of farro wheat, Triticum turgidum ssp. dicoccum, in celiac disease patients.

BACKGROUND & AIMS: Celiac disease is a gluten sensitive disorder that occurs in genetically susceptible individuals. The present study deals with variation in the immune response of mucosal T-cells from celiac children to prolamins extracted from nine landraces of farro wheat (Triticum turgidum ssp. dicoccum) with contrasting storage protein compositions. METHODS: The prolamin fraction from nine 'dicoccum' wheat landraces was subjected to peptic-tryptic digestion and supplied to T-cells from mucosal explants of four celiac patients. Immune reactions in terms of cell proliferation and INF-gamma secretion by intestinal T lymphocytes were then determined. RESULTS: T-cell lines exposed to digested prolamins from landraces L5563, L5558 and L5540 showed negligible proliferative responses and released INF-gamma amounts similar to that of untreated control cells. By contrast, landraces Ersa 6, Ersa 8, Leonessa 4 and Leonessa 5 proved to be very active in triggering the immune responses, whereas landraces Filosini and Prometeo exhibited an intermediate behavior. One-dimensional fractionations by A-PAGE or SDS-PAGE revealed distinctive prolamin patterns amongst the landraces analysed. CONCLUSIONS: 'Dicoccum' wheat represents a heterogeneous species showing a wide variation in both prolamin composition and T-cell immunological activation, some 'dicoccum' landraces being poor in or devoid of noxious gluten proteins.