Cell-mediated immunity to gluten fraction III in adult coeliac disease.

Peripheral blood lymphocytes were obtained from twenty-seven healthy control subjects, twenty-one coeliac patients on a gluten-free diet and fourteen patients on a normal diet. When the cells were cultured in vitro in the presence of 2 and 4 mg of gluten fraction III, there were significant increases in the mean ratios of response for lymphocytes from gluten-free coeliacs compared to healthy controls after 4, 5 and 6 days of culture, but for those on a normal diet significant increases were found only when using 4 mg of gluten on the 4th and 5th days of culture. When three further patients were changed from a normal to a gluten-free diet, the ratios of response for their lymphocytes increased. The results suggest that certain coeliacs may exhibit a weak delayed hypersensitivity reaction to gluten. Its more ready demonstration in patients on a gluten-free diet could be explained on the release of sensitized lymphocytes from the intestinal mucosa into the peripheral circulation after gluten withdrawal.