IFL-ANTIGLIADIN AAD ELISA-ANTIGLIADIN ANTIBODIES RECOGNIZE DIFFERENT ANTIGENIC REACTIVITIES FROM THOSE OF R1-ANTIRETICULIN AND ANTIENDOMYSIAL ANTIBODIES

In order to establish whether antigliadin antibodies, detected by indi rect imnunofluorescence (IFL-AGA), display the same antibody reactivit y as ELISA-AGA or whether they cross-react with reticulin antibodies ( R1-ARA and antiendomysial - EmA), sera from 16 untreated coeliac patie nts were repeatedly absorbed with crude gliadin dissolved in ethanol/w ater solution. The comparison between antibody activities before and a fter absorption demonstrated that IFL-AGA and ELISA-AGA are nothing bu t a single antibody, as both of them completely disappeared or markedl y reduced their titre after incubation with crude gliadin. Moreover, A GA reactivity differs from the reactivity of antibodies directed again st reticulin, as R1-ARA and EmA titres were not affected by crude glia din absorption. The absolute absence of cross-reactivity between IFL-A GA and R1-ARA is further confirmed by the removal of the former and pe rsistence of the latter after gliadin absorption in the 9 sera positiv e for both antibodies, Sera of coeliac patients, therefore, show only two discrete antibody reactivities, one directed to gliadin and the ot her to reticulin components.