Pepsin-trypsin resistant gliadin (PT-gliadin) promotes intestinal tissue inflammation and increases paracellular permeability of immunogenic gliadin peptides into the lamina propria. This leads to the complications seen in the pathogenesis of celiac disease (CD). In this study, specific anti-gliadin IgY antibody was produced and evaluated for its efficacy on gliadin induced intestinal integrity impairment and proinflammatory effects on intestinal epithelial (Caco-2) cell culture model for CD.
Caco-2 (passages 20-24) monolayers were subjected to 7 experimental conditions (n=3 each): phosphate buffered saline (PBS; control), pancreatic digested-casein (PD-casein; negative control), PT-gliadin (positive control), non-specific IgY with PT-gliadin, and anti-wheat gliadin IgY with PT-gliadin at a ratio of 1:6,000, 1:3,000 and 1:1,500. Caco-2 monolayers were then evaluated for effects of gliadin and/or anti-wheat gliadin IgY after 24 h exposure. Enzyme-linked immunosorbent assay (ELISA) was used to quantify anti-inflammatory markers (TNF-α and IL-1β) 5 days after cells were exposed to PT-gliadin and/or anti-wheat gliadin IgY.
Among other conditions, anti-wheat gliadin IgY at a ratio of 1:3,000 (anti-gliadin IgY: PT-gliadin) significantly prevented gliadin toxicity on Caco-2 by maintaining intestinal integrity, inhibiting phenol red permeation, and inhibiting gliadin absorption and production of proinflammatory cytokines (TNF-α and IL-1β) as compared to PT-gliadin stimulated cultures (P < 0.05).
The anti-wheat gliadin IgY antibody produced in this study has proved to inhibit absorption of gliadin and gliadin-induced inflammatory response in Caco2 cell culture model of CD. Anti-gliadin IgY, therefore has potential to be used as an oral passive antibody therapy to treat CD.