Dong S, Hughes R C
National Institute for Medical Research, Mill Hill, London, UK.
Glycoconj J. 1997 Feb;14(2):267-74. doi: 10.1023/a:1018554124545.
Galectin-3 (formerly called Mac-2 antigen) is a approximately 30 kDa carbohydrate-binding protein expressed on the surface of inflammatory macrophages and several macrophage cell lines. We have purified from lysates of the murine macrophage cell line WEHI-3 glycoproteins that bind to a galectin-3 affinity column. Several of these receptors are labelled after biotinylation of intact cells showing their location at the cell surface. N-terminal aminoacid sequencing of intact galectin-3-binding glycoproteins isolated from preparative SDS-gels or of chemically derived fragments showed several homologies with known proteins and identification was confirmed by immunoprecipitation with specific antibodies. The glycoproteins were shown to be: the alpha-subunit(CD11b) of the CD11b/CD18 integrin(Mac-1 antigen); the lysosomal membrane glycoproteins LAMPs 1 and 2 which are known in part to be expressed at cell surfaces; the Mac-3 antigen, a mouse macrophage differentiation antigen defined by the M3/84 monoclonal antibody and related immunochemically to LAMP-2; the heavy chain of CD98, a 125 kDa heterodimeric glycoprotein identified by the 4F2/RL388 monoclonal antibodies respectively on human and mouse monocytes/macrophages and on activated T cells. Further studies showed that CD11b/CD18, CD98 and Mac-3 are major surface receptors for galectin-3 on murine peritoneal macrophages elicited by thioglycollate.
半乳糖凝集素-3（以前称为Mac-2抗原）是一种约30 kDa的碳水化合物结合蛋白，在炎性巨噬细胞和几种巨噬细胞系的表面表达。我们已从鼠巨噬细胞系WEHI-3的裂解物中纯化出与半乳糖凝集素-3亲和柱结合的糖蛋白。其中几种受体在完整细胞生物素化后被标记，显示它们位于细胞表面。从制备性SDS凝胶中分离出的完整半乳糖凝集素-3结合糖蛋白或化学衍生片段的N端氨基酸测序显示与已知蛋白有几种同源性，并用特异性抗体进行免疫沉淀证实了其鉴定。这些糖蛋白被证明是：CD11b/CD18整合素（Mac-1抗原）的α亚基（CD11b）；溶酶体膜糖蛋白LAMPs 1和2，已知它们部分在细胞表面表达；Mac-3抗原，一种由M3/84单克隆抗体定义的小鼠巨噬细胞分化抗原，与LAMP-2有免疫化学相关性；CD98的重链，一种125 kDa的异二聚体糖蛋白，分别由4F2/RL388单克隆抗体在人和小鼠单核细胞/巨噬细胞以及活化T细胞上鉴定。进一步的研究表明，CD11b/CD18、CD98和Mac-3是硫代乙醇酸盐诱导的鼠腹膜巨噬细胞上半乳糖凝集素-3的主要表面受体。
