title: Hepatocyte growth factor/scatter factor has distinct classes of binding site in heparan sulfate from mammary cells.
abstract: Hepatocyte growth factor/scatter factor (HGF/SF) is a heparan sulfate (HS)-binding growth factor and morphogen for mammary epithelial cells that is produced by mammary stromal fibroblasts. HS chains, purified as peptidoglycans from a panel of cell lines representative of the ductal epithelial cell (Huma 123), the myoepithelial cell (Huma 109), the stromal fibroblast (Rama 27), and malignant mammary epithelial cells (MCF-7 and ZR-75), were used in a biosensor-based assay to identify the classes of HGF/SF-binding sites in the polysaccharide chains. At least three distinct binding sites were identified. One site exhibits fast association and fast dissociation kinetics [kass (1.4-7.7) x 10(6) M-1 s-1; kdiss 0. 0032-0.0096 s-1] and is present on the HS from benign Huma 123 epithelial cells, Huma 109 myoepithelial-like cells, and ZR-75 malignant cells. The second binding site, found on HS from the malignant MCF-7 cells, has slower HGF/SF-binding kinetics (kass 0.20 x 10(6) M-1 s-1; kdiss 0.00055 s-1). The third binding site possesses fast association and slow dissociation kinetics (kass 1.1 x 10(6) M-1 s-1; kdiss 0.00020 s-1) and was found on the HS isolated from the culture medium of the Huma 123 benign epithelial cells. The first and second binding sites have a similar Kd, 1-3 nM, while the third binding site has a considerably higher affinity for HGF/SF (Kd 200 pM). The three binding sites seem to be mutually exclusive, since each sample of HS possessed just one of the sites.
authors.affiliation: School of Biological Sciences, Life Sciences Building, University of Liverpool, U.K.
authors.forename: H
authors.initials: H
authors.lastname: Rahmoune
authors.forename: P S
authors.initials: PS
authors.lastname: Rudland
authors.forename: J T
authors.initials: JT
authors.lastname: Gallagher
authors.forename: D G
authors.initials: DG
authors.lastname: Fernig
mesh_terms: D000818:Animals; D001665:Binding Sites; D015374:Biosensing Techniques; D001943:Breast Neoplasms; D002460:Cell Line; D004847:Epithelial Cells / Q000378:metabolism; D005347:Fibroblasts; D019812:Heparan Sulfate Proteoglycans / Q000302:isolation & purification / Q000378:metabolism*; D017228:Hepatocyte Growth Factor / Q000378:metabolism*; D006801:Humans; D007700:Kinetics; D008321:Mammary Glands, Animal / Q000166:cytology; D051381:Rats; D011956:Receptors, Cell Surface / Q000032:analysis; D014407:Tumor Cells, Cultured
chemical_list: D019812:Heparan Sulfate Proteoglycans; D011956:Receptors, Cell Surface; C086020:glycosaminoglycan receptor; D017228:Hepatocyte Growth Factor