Immunoglobulin-producing cells in jejunal mucosa of children with coeliac disease on a gluten-free diet and after gluten challenge.

The jejunal Ig-producing cell populations in a group of 12 children with established coeliac disease (CD) in remission on a gluten-free diet were compared with those of a group of 10 patients in clinical relapse after gluten challenge. Quantification of the various immunocyte classes was performed by paired immunofluorescence staining in an individually defined mucosal tissue unit constituting a 6-micron-thick and 500-micron-wide block of tissue, including the mucosa at full height from the muscularis mucosae. In the treated group the percentage IgA/IgM/IgG cell ratios were, on the average, 82.6:12.9:4.5. There were no differences in these ratios or in the absolute immunocyte numbers when compared with a group of six control patients without CD. After gluten challenge the corresponding ratios were 77.2:17.2:5.6. The median cell number per mucosal tissue unit in the IgA, IgM, and IgG class was raised 2.1, 3.8 and 2.9 times, respectively. These increases were statistically significant. Moreover, there was a significant negative correlation between the time to clinical relapse and the number of IgG cells per tissue unit after challenge. This finding indicates that locally produced antibodies of the IgG class are especially involved in the pathogenesis of CD.