Brush border and lysosomal marker enzyme profiles in duodenal mucosa from coeliac patients before and after organ culture.

Five brush border and 2 lysosomal enzymes were measured in duodenal tissue explants from 21 children and young adults (16 coeliac and 5 non-coeliac) before and after organ culture. Reduced activity of brush border enzymes and increased activity of lysosomal enzymes were recorded in flat mucosas from coeliac patients compared with remission coeliac explants and biopsy specimens from non-coeliac controls. Slightly increased activity of alkaline phosphate and sucrase was recorded during culture (24 h) of coeliac explants. Coeliac specimens in the exacerbation state showed increased activity of acid phosphatase after culture in the presence of gluten, whereas gluten did not provoke detectable alterations in brush border enzyme activities during culture unless the wet weight of material was 1.5 mg or more. In such explants lower activity of brush border enzymes was measured after in vitro gluten exposure than after culture on gluten-free medium. Mucus removed from the specimen surface after culture contained considerable amounts of brush border enzymes and reflected the variations in the tissue homogenates. Culture media contained smaller quantities of enzymes.