Article

Siglec-8. A novel eosinophil-specific member of the immunoglobulin superfamily.

The Wellcome Trust Biocentre at Dundee, Department of Biochemistry, University of Dundee, Dundee DD1 5EH, Scotland, United Kingdom.
Journal of Biological Chemistry (Impact Factor: 4.65). 02/2000; 275(2):861-6. DOI: 10.1074/jbc.275.2.861
Source: PubMed

ABSTRACT We describe the characterization of siglec-8, a novel sialic acid-binding immunoglobulin-like lectin that is expressed specifically by eosinophils. A full-length cDNA encoding siglec-8 was isolated from a human eosinophil cDNA library. Siglec-8 is predicted to contain three extracellular immunoglobulin-like domains, a transmembrane region, and a cytoplasmic tail of 47 amino acids. The siglec-8 gene mapped on chromosome 19q13.33-41, closely linked to genes encoding CD33 (siglec-3), siglec-5, siglec-6, and siglec-7. When siglec-8 was expressed on COS cells or as a recombinant protein fused to the Fc region of human IgG(1), it was able to mediate sialic acid-dependent binding to human erythrocytes and to soluble sialoglycoconjugates. Using specific monoclonal antibodies, siglec-8 could be detected only on eosinophils and hence appears to be the first example of an eosinophil-specific transmembrane receptor.

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