THE TUMOR ASSOCIATION OF A TRISACCHARIDE EPITOPE - SPECIFICITY OF ANTISERUM DEVELOPED TO GALACTOSE BETA-1-]3 N-ACETYL GLUCOSAMINE BETA-1-]3GALACTOSE

A pentasaccharide carbohydrate epitope described by Nozawa et al (1) i s expressed by 35% of the neoplastic tissue samples from patients with endometrial cancer but not by normal endometrium. This epitope was de tected using a human monoclonal antibody (HMST-1) produced by fusion o f lymphocytes from an endometrial cancer patient. We chemically linked a synthetically produced nonreducing terminal trisaccharide portion o f this pentasaccharide to bovine serum albumin to create an effective immunogen, Gal beta 1-->3GlcNAc beta 1-->3Gal-BSA. A rabbit polyclonal antibody was produced and tested against panels of tumor and normal t issues. In contrast to the results obtained with HMST-1, 100% of the e ndometrial adenocarcinomas we studied stained with this polyclonal ant iserum while normal endometrium was non-reactive. The reactivity with other types of adenocarcinomas was approximately 80%, whereas most nor mal tissues were not reactive with the antiserum. Immunological specif icity analysis was performed with structurally related carbohydrates a nd this shows the fine specificity reaction of the antiserum. This ant igen may be clinically useful for immunolocalization and for immunotar geting.