Long term exposure to gluten in coeliacs,¹ and coeliac disease (CD) diagnosis after 16 years of age² may induce type 1 diabetes (T1D) and other autoimmune disorders. Increased prevalence of CD among diabetics and their relatives is well documented.³ Early introduction of gluten to children at high risk for T1D produces T1D associated islet autoantibodies.⁴ Similarly, in the absence of overt clinical symptoms of T1D, some coeliac children produce diabetes autoantibodies in a gluten dependent manner.⁵ In diabetics, intestinal challenge with gluten produces mucosal recruitment of lymphocytes,⁶ similar to that in CD patients.⁷ In diabetics, however, there is no production of CD related anti-tissue transglutaminase antibodies (anti-tTG).⁶

We have used a phage display assay⁸ to show that in CD patients, production of anti-tTG is limited to the intestine. Here, we …