A MONOCLONAL-ANTIBODY DIRECTED AGAINST HIGH M(R) SALIVARY MUCINS RECOGNIZES THE SO3-3GAL-BETA-1-3GLCNAC MOIETY OF SULFO-LEWIS(A) - A HISTOCHEMICAL SURVEY OF HUMAN AND RAT-TISSUE

Using a panel of synthetic oligosaccharides attached to a polyacrylami de carrier, the epitope of monoclonal antibody F2, evoked to high M(r) salivary mucins, was mapped to the SO3-3Gal beta 1-3GlcNAc- moiety of the sulfo-Le(a) antigen. Using immunochemical techniques, the express ion of the FZ-epitope was investigated in a number of different isolat ed human mucin species, as well as in human and rat tissue specimens, The mAb F2 bound to high M(r) salivary mucins, cervical mucins, colon mucins and gallbladder mucins, but not to low M(r) salivary mucins nor to gastric mucins, Immunohistochemical screening of human tissues wit h mAb F2 revealed a positive reaction with a number of epithelia, incl uding the (sero)mucous salivary glands, the goblet cells of the colon, submucosal glands of the lung, the lining epithelium of cervical and esophageal glands, the suprabasal skin keratinocytes, and Hassall's co rpuscles of the thymus, No staining was found in normal breast, pancre as, small intestine, spleen, and lymph nodes, Normal gastric glands we re negative, but gastric intestinal metaplastic glands strongly staine d with the antibody, In rat tissues, mAb F2 labeled epithelial cells o f salivary glands, colon and stomach, In addition to epithelial cells, extracellular matrix components in rat thymus and skin were labeled b y mAb F2, No labeling of erythrocytes, granulocytes, lymphocytes or bo ne marrow cells was found by FACScan analysis, The present data shows a tissue specific distribution of the F2-epitope in cells from the epi thelial lineage in human and rat.