title: Natural killer group 2A (NKG2A) and natural killer group 2C (NKG2C) bind to sulfated glycans and α2,3-NeuAc-containing glycoproteins.
abstract: Killer lectin-like receptors on natural killer (NK) cells mediate cytotoxicity through glycans on target cells. We prepared recombinant glutathione S-transferase-fused extracellular lectin-like domains (AA 94-231) of natural killer group 2A (NKG2A) (rGST-NKG2A) and NKG2C (rGST-NKG2C) and determined the binding of these receptors to plates coated with heparin-conjugated bovine serum albumin (heparin-BSA) and glycoproteins. rGST-NKG2A and rGST-NKG2C directly bound to heparin-BSA with K(d) values of 20 and 40 nM, respectively. Binding of rGST-NKG2A and rGST-NKG2C to heparin-BSA was suppressed in the presence of soluble heparin, heparan sulfate, fucoidan, λ-carrageenan, and dextran sulfate. 2-O-Sulfate residues in heparin were essential for the binding of rGST-NKG2A and rGST-NKG2C. Moreover, rGST-NKG2A and rGST-NKG2C bound to multimeric sialyl Lewis X expressing transferrin secreted by HepG2 cells with K(d) values of 80 and 114 nM, respectively. This is the first report showing that NKG2A and NKG2C bind to heparin and α2,3-NeuAc-containing glycoproteins.
authors.affiliation: Department of Clinical Chemistry, Faculty of Pharmaceutical Sciences, Toho University, Miyama, Funabashi, Chiba, Japan.
authors.forename: Xin
authors.initials: X
authors.lastname: Xin
authors.forename: Koji
authors.initials: K
authors.lastname: Higai
authors.forename: Yuzo
authors.initials: Y
authors.lastname: Imaizumi
authors.forename: Chiho
authors.initials: C
authors.lastname: Suzuki
authors.forename: Kenichiro
authors.initials: K
authors.lastname: Ito
authors.forename: Ayumi
authors.initials: A
authors.lastname: Itoh
authors.forename: Sayo
authors.initials: S
authors.lastname: Matsumoto
authors.forename: Yutaro
authors.initials: Y
authors.lastname: Azuma
authors.forename: Kojiro
authors.initials: K
authors.lastname: Matsumoto
mesh_terms: D000818:Animals; D002351:Carrageenan / Q000378:metabolism; D002417:Cattle; D006023:Glycoproteins / Q000276:immunology / Q000378:metabolism*; D056945:Hep G2 Cells; D006493:Heparin / Q000378:metabolism*; D006801:Humans; D007694:Killer Cells, Natural / Q000378:metabolism*; D055650:NK Cell Lectin-Like Receptor Subfamily A / Q000378:metabolism*; D055654:NK Cell Lectin-Like Receptor Subfamily C / Q000378:metabolism*; D011134:Polysaccharides / Q000276:immunology / Q000378:metabolism*; D011485:Protein Binding / Q000276:immunology; D012709:Serum Albumin / Q000378:metabolism; D013431:Sulfates / Q000378:metabolism; D014168:Transferrin / Q000378:metabolism
chemical_list: D006023:Glycoproteins; D055650:NK Cell Lectin-Like Receptor Subfamily A; D055654:NK Cell Lectin-Like Receptor Subfamily C; D011134:Polysaccharides; D012709:Serum Albumin; D013431:Sulfates; D014168:Transferrin; D002351:Carrageenan; D006493:Heparin; C007789:fucoidan