Kelm S, Schauer R
Biol Chem Hoppe Seyler. 1986 Sep;367(9):989-98. doi: 10.1515/bchm3.1986.367.2.989.
Binding and phagocytosis of sialidase-treated cells by peritoneal macrophages is mediated by a galactose-specific receptor. So far, only cells or particles exposing terminal galactose residues were demonstrated to be ligands. We present results obtained with a newly developed radio-receptor assay, which proves both binding and uptake of glycoproteins mediated by the galactose-recognizing receptor of peritoneal macrophages. Requirement of Ca2+ for binding is used to distinguish between reversibly surface-bound and irreversibly internalized ligands. By using this approach, the uptake of the ligand is followed and its inhibition with phenylglyoxal and N-ethylmaleimide is demonstrated. Evidence was also obtained that internalization is followed by degradation of the ligand. Studies on the specificity show that only galactose is recognized but that the binding strength depends on the arrangement of galactose residues presented by the ligand.
腹膜巨噬细胞对经唾液酸酶处理的细胞的结合和吞噬作用是由半乳糖特异性受体介导的。到目前为止，只有暴露末端半乳糖残基的细胞或颗粒被证明是配体。我们展示了用新开发的放射受体分析获得的结果，该分析证明了腹膜巨噬细胞的半乳糖识别受体介导的糖蛋白的结合和摄取。结合对Ca2+的需求用于区分可逆性表面结合和不可逆内化的配体。通过使用这种方法，跟踪配体的摄取，并证明其被苯乙二醛和N-乙基马来酰亚胺抑制。还获得了证据表明内化后配体会被降解。特异性研究表明，只有半乳糖被识别，但结合强度取决于配体呈现的半乳糖残基的排列。
