Polymeric Binders Suppress Gliadin-Induced Toxicity in the Intestinal Epithelium

Abstract

Background & Aims: Celiac disease is a prevalent immune disorder caused by the ingestion of gliadin-containing grains. We investigated the ability of a polymeric binder to reverse the toxic effects induced by gliadin in human intestinal cells and gliadin-sensitive HCD4-DQ8 mice. Methods: Gliadin was neutralized by complexation to a linear copolymer of hydroxyethylmethacrylate (HEMA) and sodium 4-styrene sulfonate (SS). The ability of the polymeric binder to abrogate the damaging effect of gliadin on cell-cell contact was investigated in IEC-6, Caco-2/15, and primary cultured differentiated enterocytes. The efficacy of the polymeric binder in preventing gliadin-induced intestinal barrier dysfunction was assessed using gliadin-sensitive HLA-HCD4/DQ8 transgenic mice. Results: Poly(hydroxyethylmethacrylate-co-styrene sulfonate) [P(HEMA-co-SS)] complexed with gliadin in a relatively specific fashion. Intestinal cells exposed to gliadin underwent profound alterations in morphology and cell-cell contacts. These changes were averted by complexing the gliadin with P(HEMA-co-SS). More importantly, the P(HEMA-co-SS) hindered the digestion of gliadin by gastrointestinal enzymes, thus minimizing the formation of immunogenic peptides. Coadministration of P(HEMA-co-SS) with gliadin to HLA-HCD4/DQ8 mice attenuated gliadin-induced changes in the intestinal barrier and reduced intraepithelial lymphocyte and macrophage cell counts. Conclusions: Polymeric binders can prevent in vitro gliadin-induced epithelial toxicity and intestinal barrier dysfunction in HCD4/DQ8 mice. They have a potential role in the treatment of patients with gluten-induced disorders. © 2009 AGA Institute.