Glycan and glycosaminoglycan binding properties of stromal cell-derived factor (SDF)-1alpha.
We show here that cell surface glycosaminoglycans (GAGs) are involved in the binding of stromal cell-derived factor (SDF)-1alpha to CD4(+)lymphoid CEM or monocytic U937 cells, inasmuch as pretreating the cells with heparitinase or chondroitinase inhibits SDF-1alpha binding by 40-41% and 31-35%, respectively. Soluble heparin or chondroitin sulfate partially but significantly inhibits SDF-1alpha binding to the cells by 45-52% and 42-56%, respectively, while dextran has no significant effect. Taken together, these results indicate the role of GAGs in SDF-1alpha attachment to the cells. However, the effects of heparitinase and chondroitinase as well as those of heparin and chondroitin sulfate are not additive, which suggests that SDF-1alpha may attach to the cells through different GAGs, and also through other ligands. Soluble mannan also inhibits SDF-1alpha binding to the cells by 30-33%. Additivity between this effect and that of heparin or chondroitin sulfate is observed. Therefore, beside GAGs, mannose-containing species may also be involved in SDF-1alpha attachment to the cells. Accordingly, SDF-1alpha specifically binds to heparin-agarose and mannose-divinylsulfone agarose affinity matrices, and these interactions are inhibited respectively by soluble heparin, chondroitin sulfate, and mannan. We have previously shown that gp120 of X4 strain HIV-1LAI presents specific carbohydrate-binding properties for mannosylated derivatives, including mannan, and for GAGs including heparin. The present data therefore indicate that, in the same manner as HIV-1 Env, SDF-1alpha can interact with GAGs and glycans at the cell surface.
Mbemba
E
E
Laboratoire de Biologie Cellulaire JE 2138, Université Paris 13, Faculté de Médecine, 93017 Bobigny, France.
Gluckman
J C
JC
Gattegno
L
L
D000595:Amino Acid Sequence; D002460:Cell Line; D054377:Chemokine CXCL12; D019743:Chemokines, CXC / Q000737:chemistry / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D006025:Glycosaminoglycans / Q000378:metabolism*; D006801:Humans; D008969:Molecular Sequence Data; D011134:Polysaccharides / Q000378:metabolism*; D011485:Protein Binding; D012685:Sepharose / Q000031:analogs & derivatives / Q000378:metabolism
C515255:CXCL12 protein, human; D054377:Chemokine CXCL12; D019743:Chemokines, CXC; D006025:Glycosaminoglycans; D011134:Polysaccharides; C037405:heparin-sepharose; D012685:Sepharose