NKG2D and CD94 bind to heparin and sulfate-containing polysaccharides.
Killer lectin-like receptors NKG2D and CD94 on natural killer cells trigger cytotoxicity through binding of glycans on target cells including sialyl Lewis X antigen. We previously reported that NKG2D and CD94 recognize alpha2,3-linked NeuAc on multi-antennary N-glycans. Here we further investigated polysaccharide binding by these receptors, using glutathione-S-transferase-fused extracellular domains of NKG2D AA 73-216 (rNKG2Dlec) and CD94 AA 68-179 (rCD94lec). We found that rNKG2Dlec and rCD94lec bind in a dose-dependent manner to plates coated with heparin-conjugated bovine serum albumin (heparin-BSA). Binding to heparin-BSA was suppressed by soluble sulfate-containing polysaccharides, but minimally impacted by 2-O-, 6-O-, and 2-N-desulfated heparin. Mutagenesis revealed that (152)Y and (199)Y of NKG2D and (144)F, (160)N, and (166)C of CD94 were critical for binding to heparin-BSA. The present manuscript provides the first evidence that NKG2D and CD94 bind to heparin and sulfate-containing polysaccharides.
Higai
Koji
K
Department of Clinical Chemistry, School of Pharmaceutical Sciences, Toho University, Miyama 2-2-1, Funabashi, Chiba 247-8510, Japan. koji@phar.toho-u.ac.jp
Imaizumi
Yuzo
Y
Suzuki
Chiho
C
Azuma
Yutaro
Y
Matsumoto
Kojiro
K
D002460:Cell Line; D004252:DNA Mutational Analysis; D005982:Glutathione Transferase / Q000378:metabolism; D006493:Heparin / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D016296:Mutagenesis; D051920:NK Cell Lectin-Like Receptor Subfamily D / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D055655:NK Cell Lectin-Like Receptor Subfamily K / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D012710:Serum Albumin, Bovine / Q000737:chemistry / Q000378:metabolism; D013431:Sulfates / Q000737:chemistry / Q000378:metabolism*
C497869:KLRD1 protein, human; C527085:KLRK1 protein, human; D051920:NK Cell Lectin-Like Receptor Subfamily D; D055655:NK Cell Lectin-Like Receptor Subfamily K; D013431:Sulfates; D012710:Serum Albumin, Bovine; D006493:Heparin; D005982:Glutathione Transferase