Celiac disease.

Clinically, celiac disease has always been regarded as a wasting, malabsorptive disorder due to disease of the small intestinal mucosa. It has been difficult for clinicians to recognize that this condition is primarily due to sensitization of mesenteric T lymphocytes to wheat protein (gluten) in genetically predisposed (DQ2+) individuals. On contact with dietary-derived gluten in the upper intestine, these sensitized T lymphocytes are activated leading to inflammation of and morphologically altered mucosal architecture: the latter reverts to normal with a gluten-free diet. The circulation of sensitized T lymphocytes to other parts of the intestinal mucosa explains why identical immunopathological inflammation can be induced in ileal and rectal mucosa. It appears, then, that in predisposed DQ2+ subjects, mesenteric T lymphocytes recognize gluten as foreign (non-self) antigen, thereby inducing mucosal pathology secondary to the initiating lymphocyte-protein interaction, analogously to the mucosal lesions that typify graft-vs-host reactions, or nematode or Giaraia infestations. Today, as this article describes, we recognize that celiac disease often exists in a subclinical, or "compensated-latent," form, or with symptoms that do not immediately suggest an origin in the gastrointestinal tract.