Sialoside specificity of the siglec family assessed using novel multivalent probes: identification of potent inhibitors of myelin-associated glycoprotein.
Ten of the 11 known human siglecs or their murine orthologs have been evaluated for their specificity for over 25 synthetic sialosides representing most of the major sequences terminating carbohydrate groups of glycoproteins and glycolipids. Analysis has been performed using a novel multivalent platform comprising biotinylated sialosides bound to a streptavidin-alkaline phosphatase conjugate. Each siglec was found to have a unique specificity for binding 16 different sialoside-streptavidin-alkaline phosphatase probes. The relative affinities of monovalent sialosides were assessed for each siglec in competitive inhibition studies. The quantitative data obtained allows a detailed analysis of each siglec for the relative importance of sialic acid and the penultimate oligosaccharide sequence on binding affinity and specificity. Most remarkable was the finding that myelin-associated glycoprotein (Siglec-4) binds with 500-10,000-fold higher affinity to a series of mono- and di-sialylated derivatives of the O-linked T-antigen (Galbeta(1-3)-GalNAc(alpha)OThr) as compared with alpha-methyl-NeuAc.
Blixt
Ola
O
Scripps Research Institute, Department of Molecular Biology, La Jolla, California 92037, USA.
Collins
Brian E
BE
van den Nieuwenhof
Ingrid M
IM
Crocker
Paul R
PR
Paulson
James C
JC
D000469:Alkaline Phosphatase; D000818:Animals; D015703:Antigens, CD / Q000235:genetics / Q000378:metabolism; D000944:Antigens, Differentiation, B-Lymphocyte / Q000235:genetics / Q000378:metabolism; D015214:Antigens, Differentiation, Myelomonocytic / Q000235:genetics / Q000378:metabolism; D016466:CHO Cells; D002240:Carbohydrate Sequence; D015815:Cell Adhesion Molecules; D002678:Chimera; D006224:Cricetinae; D004797:Enzyme-Linked Immunosorbent Assay; D005697:Galactosides / Q000138:chemical synthesis / Q000378:metabolism; D006017:Glycolipids / Q000138:chemical synthesis / Q000378:metabolism; D006023:Glycoproteins / Q000138:chemical synthesis / Q000378:metabolism; D006801:Humans; D037102:Lectins / Q000235:genetics / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008969:Molecular Sequence Data; D019158:N-Acetylneuraminic Acid / Q000378:metabolism*; D011485:Protein Binding; D011971:Receptors, Immunologic / Q000235:genetics / Q000378:metabolism*; D063267:Sialic Acid Binding Ig-like Lectin 1; D051918:Sialic Acid Binding Ig-like Lectin 2; D063265:Sialic Acid Binding Immunoglobulin-like Lectins; D019809:Streptavidin
D015703:Antigens, CD; D000944:Antigens, Differentiation, B-Lymphocyte; D015214:Antigens, Differentiation, Myelomonocytic; C497867:CD22 protein, human; C497868:Cd22 protein, mouse; D015815:Cell Adhesion Molecules; D005697:Galactosides; D006017:Glycolipids; D006023:Glycoproteins; D037102:Lectins; D008562:Membrane Glycoproteins; D011971:Receptors, Immunologic; C571166:SIGLEC1 protein, human; C114531:SIGLEC5 protein, human; C120775:SIGLEC6 protein, human; C402206:SIGLEC7 protein, human; C403967:SIGLEC8 protein, human; C412227:SIGLEC9 protein, human; D063267:Sialic Acid Binding Ig-like Lectin 1; D051918:Sialic Acid Binding Ig-like Lectin 2; D063265:Sialic Acid Binding Immunoglobulin-like Lectins; C571167:Siglec1 protein, mouse; D019809:Streptavidin; D000469:Alkaline Phosphatase; D019158:N-Acetylneuraminic Acid