title: SIGLEC-4 (MAG) Antagonists: From the Natural Carbohydrate Epitope to Glycomimetics.
abstract: Siglec-4, also known as myelin-associated glycoprotein (MAG), is a member of the siglec (sialic acid-binding immunoglobulin-like lectins) family. MAG binds with high preference to sialic acids α(2-3)-linked to D-galactose. Although the involvement and relevance of its sialic acid binding activity is still controversial, it could be demonstrated that interactions of MAG with sialylated gangliosides play an important role in axon stability and regeneration. In this article we describe in detail our current understanding of the biological role and the carbohydrate specificity of siglec-4. Furthermore, this review compiles the intensive research efforts leading from the identification of the minimal oligosaccharide binding epitope in gangliosides via micromolar oligosaccharide mimics to the development of small molecular weight and more drug-like sialic acid derivatives binding with low nanomolar affinities. Such compounds will be useful to elucidate MAG's biological functions, which are currently not fully understood.
authors.affiliation: Institute of Molecular Pharmacy, Pharmacenter, University of Basel, Klingelbergstrasse 50, CH-4056, Basel, Switzerland.
authors.forename: Oliver
authors.initials: O
authors.lastname: Schwardt
authors.forename: Soerge
authors.initials: S
authors.lastname: Kelm
authors.forename: Beat
authors.initials: B
authors.lastname: Ernst
mesh_terms: D000595:Amino Acid Sequence; D032701:Biomimetics / Q000379:methods; D002240:Carbohydrate Sequence; D000939:Epitopes / Q000737:chemistry / Q000378:metabolism; D005732:Gangliosides / Q000737:chemistry* / Q000378:metabolism; D054794:Glycomics / Q000379:methods; D006801:Humans; D018716:Molecular Mimicry; D008969:Molecular Sequence Data; D018992:Myelin-Associated Glycoprotein / Q000037:antagonists & inhibitors* / Q000737:chemistry / Q000378:metabolism; D009844:Oligosaccharides / Q000737:chemistry* / Q000378:metabolism; D011485:Protein Binding; D017386:Sequence Homology, Amino Acid; D012794:Sialic Acids / Q000737:chemistry* / Q000378:metabolism; D054852:Small Molecule Libraries / Q000138:chemical synthesis / Q000737:chemistry*; D013329:Structure-Activity Relationship
chemical_list: D000939:Epitopes; D005732:Gangliosides; D018992:Myelin-Associated Glycoprotein; D009844:Oligosaccharides; D012794:Sialic Acids; D054852:Small Molecule Libraries; C016735:sialooligosaccharides