PUB - Publikationen an der Universität Bielefeld

The isolation and structural characterization of fucosylated neolacto-series gangliosides with linear poly-N-acetyllactosaminyl chains from normal human granulocytes is described. Gangliosides were purified by consecutive use of anion exchange HPLC on Fractogel TMAE-650(S), adsorption and reversed phase HPLC on Nucleosil 50-7 and Nucleosil 7C(18) columns, respectively, TLC immunostaining with carbohydrate specific monoclonal antibodies, fast atom bombardment-mass spectrometry (FAB-MS) of the permethylated derivatives and gas chromatography-electron impact mass spectrometry (GC-EIMS) of partially methylated alditol acetates were used for structure elucidations, One ganglioside was identified as sialyl Lewis(x) antigen with nLcOse(6)Cer core, Neu5-Ac alpha 2-3Gal beta 1-4(Fuc alpha 1-3)GlcNAc beta 1-3Gal beta 1-4Glc NAc beta 1-3Gal beta 1-4Glc beta 1-1Cer. Furthermore, monosialylated ceramide: deca-, undeca-, dodeca- and tridecasaccharides with three (nLcOse(8)Cer) and four (nLcOse(10)Cer) linear lactosaminyl repeats were identified, carrying one to three fucoses. The ceramide portions were found to contain C-18 sphingosine and predominantly C-16:0 fatty acids, All monosialogangliosides were homogenous concerning their terminal alpha 2-3Neu5Ac-sialylation, but different in their fucosylation status, Beside VI(3)Neu5Ac, V(3)Fuc-nLcOse(6)Cer, in two of the fucosylated polylactosaminyl ganglioside fractions the sialyl Lewis(x) epitope was found, whereas five species expressed the terminal VIM-2 motif. The role of protein linked sialyl Lewis(x) epitope of human granulocytes as a ligand for endothelial leukocyte adhesion molecule-1 (ELAM-1; E-selectin) and platelet activation-dependent granule external membrane protein (PADGEM; P-selectin) is well documented, However, the involvement of endothelial cells E- and/or P-selectin mediated cell-cell adhesion via lipid bound sialyl Lewis(x) and/or VIM-2 epitopes on human granulocytes has to be proved in further investigations.