title: Histo-blood group antigens in human fetal thymus and in thymomas.
abstract: The glycosylation of epithelial cell surface antigens follows cellular differentiation, and changes in the pattern of expression are seen in various premalignant and malignant epithelial lesions. The distribution of type-2 chain ABH-carbohydrate structures (N-acetyl-lactosamine, H-type 2 chain, Le-y, Le-x and sialyl-Le-x) of the ABO-histo-blood group system was investigated in 19 normal fetal thymuses (gestational age 16 to 39 weeks) and in 19 thymomas in order to study possible tumor-associated changes in the glycosylation pattern. The material was investigated by immunochemical stainings of formalin-fixed paraffin-imbedded tissue using monoclonal antibodies with defined specificity. In fetal thymus the epithelial cells of the medulla and the Hassal's bodies strongly expressed elongated carbohydrate structures (Le-y, Le-x and sialyl-Le-x). In a few cases the cortical epithelial cells weakly expressed Le-x and sialyl-Le-x. Compared with fetal thymus 16 of the thymomas showed a total loss, or a very much reduced expression of elongated carbohydrate structures. Three thymomas, which histologically had been reclassified according to Kirchner & Müller-Hermelink (14) as high grade thymic carcinomas, revealed strong expression of Le-y, moderate expression of Le-x and weak expression of sialyl-Le-x. This is of interest as in other tumors Le-y is correlated with increased cell motility and with poor prognosis.
authors.affiliation: Department of Pathology, Hillerød Hospital, Denmark.
authors.forename: P
authors.initials: P
authors.lastname: Engel
authors.forename: E
authors.initials: E
authors.lastname: Dabelsteen
authors.forename: D
authors.initials: D
authors.lastname: Francis
authors.forename: N
authors.initials: N
authors.lastname: Graem
mesh_terms: D000017:ABO Blood-Group System / Q000378:metabolism; D001789:Blood Group Antigens / Q000378:metabolism*; D050260:Carbohydrate Metabolism; D002240:Carbohydrate Sequence; D006031:Glycosylation; D006801:Humans; D007124:Immunoenzyme Techniques; D008969:Molecular Sequence Data; D013945:Thymoma / Q000276:immunology / Q000378:metabolism*; D013950:Thymus Gland / Q000196:embryology* / Q000276:immunology / Q000378:metabolism*; D013953:Thymus Neoplasms / Q000276:immunology / Q000378:metabolism*
chemical_list: D000017:ABO Blood-Group System; D001789:Blood Group Antigens