title: Galectin-1 is expressed by thymic epithelial cells in myasthenia gravis.
abstract: Galectin-1, a member of a family of carbohydrate binding proteins, is synthesized by thymic epithelial cells in normal juvenile thymus, and mediates adhesion of immature T cells to thymic epithelium. Because cell adhesion molecules are proposed to play a role in the thymic hyperplasia and neoplasia seen in the autoimmune disease myasthenia gravis, we examined the expression of galectin-1 in myasthenic thymi. We detected abundant galectin-1 expression in thymic epithelial cells in 27 hyperplastic and neoplastic thymi from patients with myasthenia gravis. Primary cultures of neoplastic epithelial cells from a thymoma continued to express galectin-1, and bound immature T cells; T cell binding was inhibited by the addition of the beta-galactosides lactose and thiodigalactoside, suggesting that galectin-1 on the thymoma cells and a saccharide ligand on the T cells participated in cell-cell adhesion. Expression of galectin-1 by thymic epithelial cells may play a role in the thymic pathology seen in myasthenia gravis.
authors.affiliation: Neuropsychiatric Institute, UCLA School of Medicine 90095, USA.
authors.forename: C
authors.initials: C
authors.lastname: Hafer-Macko
authors.forename: M
authors.initials: M
authors.lastname: Pang
authors.forename: J J
authors.initials: JJ
authors.lastname: Seilhamer
authors.forename: L G
authors.initials: LG
authors.lastname: Baum
mesh_terms: D002448:Cell Adhesion; D004847:Epithelial Cells; D004848:Epithelium / Q000378:metabolism; D037483:Galectin 1; D006388:Hemagglutinins / Q000378:metabolism*; D006801:Humans; D009157:Myasthenia Gravis / Q000378:metabolism*; D013601:T-Lymphocytes / Q000166:cytology; D013945:Thymoma / Q000378:metabolism / Q000473:pathology; D013950:Thymus Gland / Q000166:cytology / Q000378:metabolism* / Q000601:surgery; D014407:Tumor Cells, Cultured; D001616:beta-Galactosidase / Q000378:metabolism
chemical_list: D037483:Galectin 1; D006388:Hemagglutinins; D001616:beta-Galactosidase