Identification of a major carbohydrate capping group of the L-selectin ligand on high endothelial venules in human lymph nodes as 6-sulfo sialyl Lewis X.
We investigated the molecular species of sulfated sialyl Lewis X determinants, the putative L-selectin ligand, expressed on high endothelial venules (HEV) in human lymph nodes. Comparison of the reactivity pattern of HEV with the reactivity of the pure 6-sulfo, 6'-sulfo, or 6,6'-bissulfo sialyl Lewis X determinant with hitherto known anti-sialyl Lewis X antibodies strongly suggested 6-sulfo sialyl Lewis X to be the best candidate for the major sulfated sialyl Lewis X determinant on HEV, followed by 6,6'-bissulfo sialyl Lewis X, whereas 6'-sulfo sialyl Lewis X was unlikely. We newly generated monoclonal antibodies (mAbs) G152 and G72 directed against 6-sulfo sialyl Lewis X, which intensely labeled HEV in immunohistochemical examination and inhibited binding of recombinant L-selectin-IgG to HEV, suggesting that the determinant serves as a ligand for L-selectin. To test the concomitant expression of 6, 6'-bissulfo sialyl Lewis X, specific mAbs (G2706, G27011, G27037, and G27039) were generated, but all antibodies failed to react to HEV. Next, we established mAbs (AG97 and AG273) directed against 6-sulfo Lewis X, the asialo form of 6-sulfo sialyl Lewis X. The antibodies were not reactive to untreated HEV, but strongly reacted to sialidase-treated HEV. This indicated the predominance of the sialylated form of 6-sulfo sialyl Lewis X and minimal expression of its asialo form, corroborating that it was synthesized by fucosyltransferase VII, the isoenzyme that preferentially produces the sialylated form of the determinant.
Mitsuoka
C
C
Program of Experimental Pathology,, Japan.
Sawada-Kasugai
M
M
Ando-Furui
K
K
Izawa
M
M
Nakanishi
H
H
Nakamura
S
S
Ishida
H
H
Kiso
M
M
Kannagi
R
R
D000911:Antibodies, Monoclonal / Q000276:immunology; D002240:Carbohydrate Sequence; D002241:Carbohydrates / Q000737:chemistry*; D004730:Endothelium, Vascular / Q000378:metabolism*; D006801:Humans; D019041:L-Selectin / Q000737:chemistry* / Q000378:metabolism; D016256:Lewis X Antigen / Q000031:analogs & derivatives; D008024:Ligands; D008198:Lymph Nodes / Q000098:blood supply*; D008969:Molecular Sequence Data; D009439:Neuraminidase / Q000378:metabolism; D009844:Oligosaccharides / Q000737:chemistry* / Q000276:immunology / Q000378:metabolism; D000080506:Sialyl Lewis X Antigen / Q000031:analogs & derivatives; D014407:Tumor Cells, Cultured; D014699:Venules / Q000378:metabolism*
C086949:6'-sulfated sialyl Lewis x; D000911:Antibodies, Monoclonal; D002241:Carbohydrates; D016256:Lewis X Antigen; D008024:Ligands; D009844:Oligosaccharides; D000080506:Sialyl Lewis X Antigen; D019041:L-Selectin; D009439:Neuraminidase