title: Carbohydrate microarrays reveal sulphation as a modulator of siglec binding.
abstract: Siglecs are receptors on cells of the immune, haemopoietic, and nervous systems that recognize sialyl-glycans with differing preferences for sialic acid linkage and oligosaccharide backbone sequence. We investigate here siglec binding using microarrays of Lewis(x) (Le(x))- and 3'-sialyl-Le(x)-related probes with different sulphation patterns. These include sulphation at position 3 of the terminal galactose of Le(x), position 6 of the galactose of Le(x) and sialyl-Le(x), position 6 of N-acetylglucosamine of Le(x) and sialyl-Le(x), or both positions of sialyl-Le(x). Recombinant soluble forms of five siglecs have been investigated: human Siglec-7, -8, -9, and murine Siglec-F and CD22 (Siglec-2). Each siglec has a different binding pattern. Unlike two C-type lectins of leukocytes, L-selectin and Langerin, which also bind to sulphated analogues of sialyl-Le(x), the siglecs do not give detectable binding signals with sulphated analogues that are lacking sialic acid. The sulphate groups modulate, however, positively or negatively the siglec binding intensities to the sialyl-Le(x) sequence.
authors.affiliation: The Glycosciences Laboratory, Imperial College Faculty of Medicine, Northwick Park and St Mark's Campus, Harrow HA1 3UJ, UK.
authors.forename: María Asunción
authors.initials: MA
authors.lastname: Campanero-Rhodes
authors.forename: Robert A
authors.initials: RA
authors.lastname: Childs
authors.forename: Makato
authors.initials: M
authors.lastname: Kiso
authors.forename: Shiro
authors.initials: S
authors.lastname: Komba
authors.forename: Christine
authors.initials: C
authors.lastname: Le Narvor
authors.forename: Joanna
authors.initials: J
authors.lastname: Warren
authors.forename: Diana
authors.initials: D
authors.lastname: Otto
authors.forename: Paul R
authors.initials: PR
authors.lastname: Crocker
authors.forename: Ten
authors.initials: T
authors.lastname: Feizi
mesh_terms: D000818:Animals; D006801:Humans; D037102:Lectins / Q000737:chemistry*; D051379:Mice; D046228:Microarray Analysis / Q000379:methods*; D015335:Molecular Probes / Q000737:chemistry*; D009844:Oligosaccharides / Q000737:chemistry*; D000080506:Sialyl Lewis X Antigen; D013431:Sulfates / Q000737:chemistry*
chemical_list: D037102:Lectins; D015335:Molecular Probes; D009844:Oligosaccharides; D000080506:Sialyl Lewis X Antigen; D013431:Sulfates