title: Molecular and functional characterization of porcine Siglec-3/CD33 and analysis of its expression in blood and tissues.
abstract: A cDNA clone encoding a 380 a-a type 1 transmembrane protein with homology to human Siglec-3/CD33 was obtained from a swine small intestine library. An analysis of protein sequence identified two immunoglobulin-like domains, a transmembrane region, and a carboxi-terminal tail with two tyrosine-based signalling motifs. Binding assays of Siglec-3 transfected CHO cells to polyacrylamide glycoconjugates showed a preference for α2-6-linked sialic acids. Using mAbs raised against a fragment containing the two Ig-like domains, porcine Siglec-3 was found to be expressed on monocytes and granulocytes, and their bone marrow precursors. It was also detected in lymph node, splenic and alveolar macrophages. MAbs immunoprecipitated, from granulocyte lysates, a protein of 51-60 kDa under both non-reducing and reducing conditions. MAbs were also used to analyse functional activity of Siglec-3 on bone marrow and blood cells. Engagement of Siglec-3 by mAb had no apparent effect on cell proliferation or cytokine production.
authors.affiliation: Dpto. de Biotecnología, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Ctra de la Coruña Km 7.5, Madrid 28040, Spain.
authors.forename: B
authors.initials: B
authors.lastname: Álvarez
authors.affiliation: Dpto. de Biotecnología, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Ctra de la Coruña Km 7.5, Madrid 28040, Spain.
authors.forename: Z
authors.initials: Z
authors.lastname: Escalona
authors.affiliation: National Institute of Agrobiological Sciences (NIAS), 2 Ikenodai, Tsukuba, Ibaraki 305-8602, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Uenishi
authors.affiliation: Institute of Japan Association for Techno-innovation in Agriculture, Forestry and Fisheries, 446-1 Ippaizuka, Kamiyokoba, Tsukuba, Ibaraki 305-0854, Japan.
authors.forename: D
authors.initials: D
authors.lastname: Toki
authors.affiliation: Dpto. de Biotecnología, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Ctra de la Coruña Km 7.5, Madrid 28040, Spain.
authors.forename: C
authors.initials: C
authors.lastname: Revilla
authors.affiliation: Dpto. de Biotecnología, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Ctra de la Coruña Km 7.5, Madrid 28040, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Yuste
authors.affiliation: Dpto. de Biología Celular y de Inmunología, Facultad de Medicina, Universidad Complutense de Madrid, Avda. Complutense s/n, Madrid 28040, Spain.
authors.forename: M Gómez
authors.initials: MG
authors.lastname: Del Moral
authors.affiliation: Dpto. de Biotecnología, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Ctra de la Coruña Km 7.5, Madrid 28040, Spain.
authors.forename: F
authors.initials: F
authors.lastname: Alonso
authors.affiliation: Dpto. de Biotecnología, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Ctra de la Coruña Km 7.5, Madrid 28040, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Ezquerra
authors.affiliation: Dpto. de Biotecnología, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Ctra de la Coruña Km 7.5, Madrid 28040, Spain. Electronic address: juncal@inia.es.
authors.forename: J
authors.initials: J
authors.lastname: Domínguez
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000378:metabolism; D001773:Blood Cells / Q000276:immunology*; D016466:CHO Cells; D003412:Cricetulus; D020869:Gene Expression Profiling; D006801:Humans; D007421:Intestine, Small / Q000502:physiology*; D022423:Myeloid Cells / Q000276:immunology*; D019158:N-Acetylneuraminic Acid / Q000378:metabolism; D011485:Protein Binding; D017386:Sequence Homology, Amino Acid; D063268:Sialic Acid Binding Ig-like Lectin 3 / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D013552:Swine / Q000276:immunology*; D019076:Transgenes / Q000235:genetics
chemical_list: D000911:Antibodies, Monoclonal; D063268:Sialic Acid Binding Ig-like Lectin 3; D019158:N-Acetylneuraminic Acid
keywords: CD33; Monoclonal antibody; Monocyte; Myeloid cells; Siglec-3; Swine