Gut endocrine cell population in coeliac disease estimated by immunocytochemistry using a monoclonal antibody to chromogranin.

Abnormalities of gut endocrine responses, as well as changes in the number of different endocrine cell types, have been reported convincingly in coeliac patients. Nevertheless, no estimation of total numbers of gut endocrine cells has yet been made in well defined groups of coeliacs. In this study, we have visualised all endocrine cell types in jejunal biopsies from coeliac patients with active and quiescent disease as well as in controls, using a monoclonal antibody to chromogranin. This protein was purified originally from bovine adrenal medulla and is known to be a reliable marker for all endocrine cells of the gut. The following groups were considered: (a) nine coeliacs with active illness, (b) 10 coeliacs under gluten-free diet, (c) eight coeliacs receiving gluten challenge, (d) five non-coeliacs (controls). Histological (haematoxylin and eosin) and immunocytochemical (peroxidase anti-peroxidase) stains were applied to 3 micron paraffin sections. Quantitative estimation of endocrine cell density was made using four different methods in order to evaluate the results fully (number of cells/mm2, number of cells/visual field, number of cells/8 crypts-villi, number of cells/unit of length of muscularis mucosae). In patient groups (a) and (c), coeliacs with active disease and coeliacs on gluten challenge diet respectively, a significantly higher number of endocrine cells was observed in comparison with normal controls (group d). In group (b) patients, coeliacs on gluten-free diet, no significant changes in the number of endocrine cells were observed in comparison with controls. Our results show that a significant increase in endocrine cell density exists in coeliacs with active illness (groups a and c), in comparison with controls. This condition is resolved in coeliacs receiving a gluten-free diet (group b).