Immunohistochemical investigation with carbohydrate monoclonal antibodies in cystic fibrosis

Background. Cystic fibrosis is one of the most common inherited diseases in Europe. In patients with cystic fibrosis, the serum levels of the tumour m arker antigens CA19-9 and CA50, which are normally found in the epithelium of many organs, are increased. No such finding has been reported for CA245 another ubiquitous tumour marker antigen. We set out to investigate immunoh istochemically the correlation of CA19-9 and CA50 with cystic fibrosis and to compare the effect of antibodies against these three tumour markers with regard to improved immunohistochemical results. Materials and Methods. Par affin-embedded tissue from different organs of 18 patients with cystic fibr osis was studied. Immunohistochemical reactions were performed with antibod ies against CA19-9, CA50 and CA242 followed by visualisation with the ABC m ethod. Results. Immunohistochemical reactions in different tissues were uni form. Anti-CA19-9 reacted less intensive than anti-CA50 and anti-CA242. The antibodies generally bound to cell membranes and compounds of the cytoplas m. Conclusions. This study demonstrates immunohistochemically the epitopes of monoclonal carbohydrate antigens (CA-19-9, CA-50 and CA 242) in cystic f ibrosis for the first time. We also supposed that cystic fibrosis patients show ina eased serum levels of CA242. However; none of the three antibodies investigated seems suitable for the immunohistochemical diagnosis of cysti c fibrosis.