[Inhibition of the cytotoxic activity of natural killer cells by glycosphingolipids. Effect of the structure of carbohydrate chains].
The ability of various glycosphingolipids to inhibit the cytotoxic activity of natural killer (NK) cells was studied. The inhibitory effect was found to depend on the structure and concentration of the glycosphingolipids. Gangliosides SiaLacCer inhibited the NK activity most effectively and their inhibitory effect depended on the structure of sialic acids: the N-acetyl form was more active than the N-glycoloyl form. Elongation of the carbohydrate chain decreased the inhibitory effect and monosialogangliosides NeuGcGgOse3Cer and NeuAcGgOse4Cer were practically inactive. The inhibitory ability of disialogangliosides depended on the structure of the carbohydrate chain as well as on the structure and attachment site of the sialic acids. Previously it was found that ganglioside (NeuAc)2LacCer, which is absent or very low in normal blood, is produced by a number of tumors and alongside with NeuAcLacCer is present in elevated amounts in the blood of tumor-bearing subjects. Elevated concentration of these gangliosides in the blood of tumor hosts may inhibit apparently the NK activity and thus contribute to the escape of tumor cells from host immune surveillance.
D000818:Animals; D002240:Carbohydrate Sequence; D002478:Cells, Cultured; D006224:Cricetinae; D003602:Cytotoxicity, Immunologic / Q000187:drug effects; D006028:Glycosphingolipids / Q000494:pharmacology*; D007694:Killer Cells, Natural / Q000187:drug effects / Q000276:immunology*; D008647:Mesocricetus; D009844:Oligosaccharides / Q000494:pharmacology*
D006028:Glycosphingolipids; D009844:Oligosaccharides
Ingibirovanie tsitotoksicheskoĭ aktivnosti estestvennykh killerov glikosfingolipidami. Vliianie struktury oligosakharidnykh tsepeĭ.