Hafer-Macko C, Pang M, Seilhamer J J, Baum L G
Neuropsychiatric Institute, UCLA School of Medicine 90095, USA.
Glycoconj J. 1996 Aug;13(4):591-7. doi: 10.1007/BF00731447.
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.
半乳糖凝集素-1是碳水化合物结合蛋白家族的一员，由正常幼年胸腺中的胸腺上皮细胞合成，并介导未成熟T细胞与胸腺上皮的黏附。由于细胞黏附分子被认为在自身免疫性疾病重症肌无力中出现的胸腺增生和肿瘤形成中起作用，我们检测了重症肌无力患者胸腺中半乳糖凝集素-1的表达。我们在27例重症肌无力患者的增生性和肿瘤性胸腺的胸腺上皮细胞中检测到丰富的半乳糖凝集素-1表达。来自胸腺瘤的肿瘤上皮细胞原代培养物持续表达半乳糖凝集素-1，并结合未成熟T细胞；添加β-半乳糖苷乳糖和硫代二半乳糖苷可抑制T细胞结合，这表明胸腺瘤细胞上的半乳糖凝集素-1和T细胞上的糖类配体参与了细胞间黏附。胸腺上皮细胞表达半乳糖凝集素-1可能在重症肌无力的胸腺病理过程中起作用。
