Celiac disease could be treated, and potentially cured, by restoring T-cell tolerance to gliadin. We investigated the safety and efficacy of negatively charged, 500 nm, poly(lactide-co-glycolide) nanoparticles encapsulating gliadin protein (TIMP-GLIA) in 3 mouse models of celiac disease. Uptake of these nanoparticles by antigen-presenting cells was shown to induce immune tolerance in other animal models of autoimmune disease.