title: Role of male reproductive tract CD52 (mrt-CD52) in reproduction.
abstract: Human CD52 antigen is a highly glycosylated molecule with an unusually small core peptide exclusively expressed on lymphocytes and mature sperm. In the male reproductive tract, it is secreted mainly from the epididymis and inserted into the sperm membrane via the glycosyl-phosphatidyl inositol (GPI) anchor during the passage of the spermatozoa through the epididymis. It has recently been found that the male reproductive tract CD52 (mrt-CD52) is a target antigen of human monoclonal antibody (Mab H6-3C4) obtained from an antisperm antibody-mediated infertile woman. The Mab H6-3C4 shows strong sperm-immobilizing activity with complement and specifically recognizes the N-linked carbohydrate epitope of sperm CD52 but not lymphocyte CD52. Lectin binding assays have revealed the presence of both O-linked as well as N-linked carbohydrate moieties in human mrt-CD52. Mouse monoclonal antibody (1 G12) reacting to human mrt-CD52 strongly inhibits penetration of human spermatozoa to the zona denuded hamster oocyte. Mouse CD52 is similar to human CD52 in biological and immunological characteristics. Male and female mice immunized with naturally-occurring mouse mrt-CD52 molecules produce antibodies against the cognate antigen yielding antisera with complement-dependent mouse sperm immobilizing activities.
authors.affiliation: Department of Obstetrics and Gynecology, Institute for Advanced Medical Sciences, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya, Hyogo 6638501, Japan. kkoyama@hyo-med.ac.jp
authors.forename: Koji
authors.initials: K
authors.lastname: Koyama
authors.forename: Koichi
authors.initials: K
authors.lastname: Ito
authors.forename: Akiko
authors.initials: A
authors.lastname: Hasegawa
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000494:pharmacology; D000918:Antibody Specificity; D015703:Antigens, CD / Q000737:chemistry / Q000276:immunology / Q000502:physiology*; D000951:Antigens, Neoplasm / Q000737:chemistry / Q000276:immunology / Q000502:physiology*; D000074301:CD52 Antigen; D004822:Epididymis / Q000276:immunology*; D005260:Female; D006023:Glycoproteins / Q000737:chemistry / Q000276:immunology / Q000502:physiology*; D006801:Humans; D007247:Infertility, Female / Q000276:immunology; D008297:Male; D051379:Mice; D012098:Reproduction / Q000502:physiology*; D013081:Sperm Motility / Q000187:drug effects; D013094:Spermatozoa / Q000187:drug effects / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D000951:Antigens, Neoplasm; D000074301:CD52 Antigen; C000613862:CD52 protein, human; D006023:Glycoproteins