title: Highly Conserved Testicular Localization of Claudin-11 in Normal and Impaired Spermatogenesis.
abstract: In this study we tested expression of tight junction proteins in human, mouse and rat and analyzed the localization of claudin-11 in testis of patients with normal and impaired spermatogenesis. Recent concepts generated in mice suggest that the stage-specifically expressed claudin-3 acts as a basal barrier, sealing the seminiferous epithelium during migration of spermatocytes. Corresponding mechanisms have never been demonstrated in humans. Testicular biopsies (n = 103) from five distinct groups were analyzed: normal spermatogenesis (NSP, n = 28), hypospermatogenesis (Hyp, n = 24), maturation arrest at the level of primary spermatocytes (MA, n = 24), Sertoli cell only syndrome (SCO, n = 19), and spermatogonial arrest (SGA, n = 8). Protein expression of claudin-3, -11 and occludin was analyzed. Human, mice and rat testis robustly express claudin-11 protein. Occludin was detected in mouse and rat and claudin-3 was found only in mice. Thus, we selected claudin-11 for further analysis of localization. In NSP, claudin-11 is located at Sertoli-Sertoli junctions and in Sertoli cell contacts towards spermatogonia. Typically, claudin-11 patches do not reach the basal membrane, unless flanked by the Sertoli cell body or patches between two Sertoli cell bodies. The amount of basal claudin-11 patches was found to be increased in impaired spermatogenesis. Only claudin-11 is expressed in all three species examined. The claudin-11 pattern is robust in man with impaired spermatogenesis, but the proportion of localization is altered in SCO and MA. We conclude that claudin-11 might represent the essential component of the BTB in human.
authors.affiliation: Justus-Liebig-University Giessen, Institute of Anatomy and Cell Biology, Aulweg 123, D-35392, Giessen, Germany.|Justus-Liebig-University Giessen, Department of Obstetrics and Gynecology, Feulgenstraße 12, D-35392, Giessen, Germany.
authors.forename: Angelika
authors.initials: A
authors.lastname: Stammler
authors.affiliation: Justus-Liebig-University Giessen, Department of Obstetrics and Gynecology, Feulgenstraße 12, D-35392, Giessen, Germany.
authors.forename: Benjamin Udo
authors.initials: BU
authors.lastname: Lüftner
authors.affiliation: University Hospital Münster, Department of Clinical Andrology, Centre of Reproductive Medicine and Andrology, Domagkstrasse 11, D-48129, Münster, Germany.
authors.forename: Sabine
authors.initials: S
authors.lastname: Kliesch
authors.affiliation: Justus-Liebig-University / UKGM Giessen, Department of Urology, Pediatric Urology and Andrology, D-35392 Giessen, Germany.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Weidner
authors.affiliation: Justus-Liebig-University Giessen, Institute of Veterinary Anatomy, Histology and Embryology, Frankfurter Straße 98, D-35392, Giessen, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Bergmann
authors.affiliation: Justus-Liebig-University Giessen, Institute of Anatomy and Cell Biology, Aulweg 123, D-35392, Giessen, Germany.
authors.forename: Ralf
authors.initials: R
authors.lastname: Middendorff
authors.affiliation: Justus-Liebig-University Giessen, Department of Obstetrics and Gynecology, Feulgenstraße 12, D-35392, Giessen, Germany.
authors.forename: Lutz
authors.initials: L
authors.lastname: Konrad
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D001814:Blood-Testis Barrier / Q000378:metabolism; D057167:Claudins / Q000378:metabolism*; D006801:Humans; D007248:Infertility, Male / Q000378:metabolism*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008875:Middle Aged; D051381:Rats; D017208:Rats, Wistar; D013091:Spermatogenesis / Q000502:physiology*; D013737:Testis / Q000378:metabolism*; D014018:Tissue Distribution; D055815:Young Adult
chemical_list: C120453:CLDN11 protein, human; D057167:Claudins