Tsuboi S, Isogai Y, Hada N, King J K, Hindsgaul O, Fukuda M
Glycobiology Program, La Jolla Cancer Research Center, The Burnham Institute, La Jolla, California 92037, USA.
J Biol Chem. 1996 Nov 1;271(44):27213-6. doi: 10.1074/jbc.271.44.27213.
In order to determine if a sulfated oligosaccharide on the cell surface can function as an L-selectin ligand, a novel approach for in vitro transfer of oligosaccharides was utilized (Srivastava, G., Kaun, K. J., Hindsgaul, O., and Palcic, M. M. (1992) J. Biol. Chem. 267, 22356-22361). CHO cells were incubated with synthetic 6'-sulfo sialyl Lex, NeuNAcalpha2-->3(sulfate-6)Galbeta1-->4(Fucalpha1-->3) GlcNAc or 6-sulfo sialyl Lex, NeuNAcalpha2-->3Galbeta1-->4[(Fucalpha1-->3)sulfate--> 6GlcNAc] oligosaccharide linked to C-6 of a fucose residue in GDP-fucose and a milk fucosyltransferase. The resultant CHO cells expressing 6'-sulfo sialyl Lex or 6-sulfo sialyl Lex on their cell surface were tested for adhesion to E-selectin and L-selectin chimeric proteins coated on plates. The results indicate that 6'-sulfo sialyl Lex supports L-selectin-mediated adhesion much better than sialyl Lex similarly tagged on the cell surface. In contrast, 6-sulfo sialyl Lex containing a sulfate group on the N-acetylglucosamine residue did not support adhesion with either selectin. These combined results suggest that 6'-sulfo sialyl Lex is a much better ligand than sialyl Lex oligosaccharide for L-selectin.
为了确定细胞表面的硫酸化寡糖是否能作为L-选择素配体发挥作用，研究采用了一种寡糖体外转移的新方法（Srivastava, G., Kaun, K. J., Hindsgaul, O., and Palcic, M. M. (1992) J. Biol. Chem. 267, 22356 - 22361）。将CHO细胞与合成的6'-磺基唾液酸化路易斯寡糖、NeuNAcalpha2-->3（硫酸酯-6）Galbeta1-->4（Fucalpha1-->3）GlcNAc或6-磺基唾液酸化路易斯寡糖、NeuNAcalpha2-->3Galbeta1-->4[（Fucalpha1-->3）硫酸酯-->6GlcNAc]寡糖一起孵育，这些寡糖与GDP-岩藻糖中的岩藻糖残基的C-6相连，并与一种牛奶岩藻糖基转移酶结合。对在细胞表面表达6'-磺基唾液酸化路易斯寡糖或6-磺基唾液酸化路易斯寡糖的所得CHO细胞进行检测，以观察其对包被在平板上的E-选择素和L-选择素嵌合蛋白的黏附情况。结果表明，6'-磺基唾液酸化路易斯寡糖比同样标记在细胞表面的唾液酸化路易斯寡糖更能支持L-选择素介导的黏附。相比之下，在N-乙酰葡糖胺残基上含有硫酸基团的6-磺基唾液酸化路易斯寡糖不支持与任何一种选择素的黏附。这些综合结果表明，对于L-选择素而言，6'-磺基唾液酸化路易斯寡糖是比唾液酸化路易斯寡糖更好的配体。
