Different glycosphingolipid composition in human neutrophil subcellular compartments.
The binding of a number of carbohydrate-recognizing ligands to glycosphingolipids and polyglycosylceramides of human neutrophil subcellular fractions (plasma membranes/secretory vesicles of resting and ionomycin-stimulated cells, specific and azurophil granules) was examined using the chromatogram binding assay. Several organelle-related differences in glycosphingolipid content were observed. The most prominent difference was a decreased content of the GM3 ganglioside in plasma membranes of activated neutrophils. Gangliosides recognized by anti-VIM-2 antibodies were detected mainly in the acid fractions of azurophil and specific granules. Slow-migrating gangliosides and polyglycosylceramides with Helicobacter pylori-binding activity were found in all acid fractions. A non-acid triglycosylceramide, recognized by Gal(alpha)4Gal-binding Escherichia coli, was detected in the plasma membrane/secretory vesicles but not in the azurophil and specific granules. Although no defined roles of glycosphingolipids have yet been conclusively established with respect to neutrophil function, the fact that many of the identified glycosphingolipids are stored in granules, is in agreement with their role as receptor structures that are exposed on the neutrophil cell surface upon fusion of granules with the plasma membrane. Accordingly, we show that neutrophil granules store specific carbohydrate epitopes that are upregulated to the plasma membrane upon cell activation.
Karlsson
A
A
Department of Medical Microbiology and Immunology, Göteborg University, P.O. Box 435, 405 30 Göteborg, Sweden.
Miller-Podraza
H
H
Johansson
P
P
Karlsson
K A
KA
Dahlgren
C
C
Teneberg
S
S
D000911:Antibodies, Monoclonal / Q000378:metabolism; D001426:Bacterial Proteins / Q000378:metabolism; D002240:Carbohydrate Sequence; D002458:Cell Fractionation; D002462:Cell Membrane / Q000737:chemistry; D006028:Glycosphingolipids / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism; D016480:Helicobacter pylori / Q000378:metabolism; D006801:Humans; D007425:Intracellular Membranes / Q000737:chemistry; D015759:Ionomycin / Q000494:pharmacology; D007476:Ionophores / Q000494:pharmacology; D037102:Lectins / Q000378:metabolism; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D018375:Neutrophil Activation; D009504:Neutrophils / Q000737:chemistry* / Q000187:drug effects / Q000648:ultrastructure
D000911:Antibodies, Monoclonal; D001426:Bacterial Proteins; D006028:Glycosphingolipids; D007476:Ionophores; D037102:Lectins; C092412:neutrophil-activating protein A, Helicobacter pylori; D015759:Ionomycin