title: Chemical Characterization of N-Linked Oligosaccharide As the Antigen Epitope Recognized by an Anti-Sperm Auto-Monoclonal Antibody, Ts4.
abstract: Ts4, an anti-sperm auto-monoclonal antibody, possesses immunoreactivity to the acrosomal region of mouse epididymal spermatozoa. In addition, the mAb shows specific immunoreactivity to reproduction-related regions such as testicular germ cells and early embryo. Our qualitative study previously showed that the antigen epitope for Ts4 contained a N-linked common oligosaccharide (OS) chain on testicular glycoproteins as determined by Western blotting for testicular glycoproteins after treatment with several glycohydrolases. Since the distribution of the Ts4-epitope is unique, the OS chain in Ts4-epitope may have role(s) in the reproductive process. The aim of this study was to clarify the molecular structure of the Ts4-epitope, particularly its OS moiety. Using Ts4 immunoprecipitation combined with liquid chromatography and multiple-stage mass spectrometry, the candidate carbohydrate structure in the Ts4-epitope is proposed to be N-linked fucosylated agalacto-biantennary with bisecting N-acetylglucosamine (GlcNAc) or with N-acetylgalactosamine-GlcNAc motif. Further binding analyses using various lectins against the mouse testicular Ts4-immunoprecipitants revealed that Phaseolus vulgaris erythroagglutinin and Pisum sativum agglutinin showed positive staining of the bands corresponding to Ts4 reactive proteins. Moreover, the immunoreactivity of Ts4 against the testicular extract was completely abrogated after digestion with β-N-acetylglucosaminidase. These results show that the Ts4-epitope contains agalacto-biantennary N-glycan with bisecting GlcNAc carrying fucose residues.
authors.affiliation: Institute for Environmental and Gender-specific Medicine, Juntendo University Graduate School of Medicine, Urayasu, Chiba, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yoshitake
authors.affiliation: Division of Biological Chemistry and Biologicals, National Institute of Health Sciences, Setagaya-ku, Tokyo, Japan.
authors.forename: Noritaka
authors.initials: N
authors.lastname: Hashii
authors.affiliation: Division of Biological Chemistry and Biologicals, National Institute of Health Sciences, Setagaya-ku, Tokyo, Japan.
authors.forename: Nana
authors.initials: N
authors.lastname: Kawasaki
authors.affiliation: Institute for Environmental and Gender-specific Medicine, Juntendo University Graduate School of Medicine, Urayasu, Chiba, Japan; Department of Obstetrics and Gynecology, Juntendo University Graduate School of Medicine, Bunkyo-ku, Tokyo, Japan.
authors.forename: Shuichiro
authors.initials: S
authors.lastname: Endo
authors.affiliation: Institute for Environmental and Gender-specific Medicine, Juntendo University Graduate School of Medicine, Urayasu, Chiba, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Takamori
authors.affiliation: Department of Obstetrics and Gynecology, Hyogo College of Medicine, Nishinomiya, Hyogo, Japan.
authors.forename: Akiko
authors.initials: A
authors.lastname: Hasegawa
authors.affiliation: Department of Obstetrics and Gynecology, Kanazawa University Graduate School of Medical Science, Kanazawa, Ishikawa, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Fujiwara
authors.affiliation: Institute for Environmental and Gender-specific Medicine, Juntendo University Graduate School of Medicine, Urayasu, Chiba, Japan; Department of Obstetrics and Gynecology, Juntendo University Graduate School of Medicine, Bunkyo-ku, Tokyo, Japan.
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Araki
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000954:Antigens, Surface / Q000276:immunology / Q000378:metabolism; D001323:Autoantibodies / Q000276:immunology*; D000939:Epitopes / Q000276:immunology*; D058851:GPI-Linked Proteins / Q000276:immunology / Q000378:metabolism; D006026:Glycoside Hydrolases / Q000378:metabolism; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D009584:Nitrogen; D009844:Oligosaccharides / Q000737:chemistry* / Q000276:immunology*; D059748:Proteolysis; D013094:Spermatozoa / Q000276:immunology*; D013737:Testis / Q000276:immunology
chemical_list: D000911:Antibodies, Monoclonal; D000954:Antigens, Surface; D001323:Autoantibodies; D000939:Epitopes; D058851:GPI-Linked Proteins; D009844:Oligosaccharides; C426726:TEX101 protein, mouse; D006026:Glycoside Hydrolases; D009584:Nitrogen