GLIADIN ACTIVATES MUCOSAL CELL-MEDIATED-IMMUNITY IN CULTURED RECTAL MUCOSA FROM CELIAC PATIENTS AND A SUBSET OF THEIR SIBLINGS

Background-CD3 and gamma delta cells in the rectal mucosa increase aft er local instillation of gluten in children with coeliac disease and i n half of their siblings. Aim-To establish an in vitro system for asse ssing immunological changes induced by gluten in the rectum. Patients and Methods-Rectal biopsy specimens obtained from 13 treated coeliac c hildren, nine of their siblings, and nine controls were cultured in vi tro with a peptic-tryptic digest of gliadin or ovalbumin, CD3 and CD25 cells were counted, and the expression of adhesion molecules evaluate d. Results-In the lamina propria of coeliac biopsy samples cultured wi th gliadin, but not in those from controls, the expression of vascular cell adhesion molecule 1 (VCAM-1) was enhanced, and the number of CD2 5 cells was significantly higher than in those cultured in medium alon e; the density of intraepithelial CD3 cells was also significantly hig her. No differences were noted in coeliac biopsy specimens cultured wi th ovalbumin. A discriminant analysis allowed correct classification o f all controls and all coeliacs but one, but three of nine siblings we re allocated to the coeliac group. Conclusions-Our data confirm that g liadin is able to activate cell mediated immunity in the rectal mucosa in coeliac patients and in a subset of their first degree relatives.