title: Expression pattern of testicular claudin-11 in infertile men.
abstract: OBJECTIVE
  To investigate the expression levels of claudin-11 mRNA and the localization of claudin-11 protein in testes of infertile men.
  
  
  METHODS
  This study included 5 men with obstructive azoospermia and 50 men with nonobstructive azoospermia who had undergone testicular sperm extraction. Testicular tissues were obtained from these men and expression levels of claudin-11 mRNA in testicular samples were determined by real-time reverse transcription-polymerase chain reaction. The localization of claudin-11 protein was analyzed by immunofluorescent staining.
  
  
  RESULTS
  Expression levels of testicular claudin-11 mRNA in nonobstructive azoospermia men were significantly greater than in obstructive azoospermia men, whereas there was no significant difference in testicular claudin-11 mRNA expression between men with and without successful sperm retrieval by testicular sperm extraction. Based on the findings of immunofluorescent staining, expression patterns of claudin-11 protein could be divided into normal (localization to basal component of seminiferous tubules) and abnormal patterns (diffuse expression in Sertoli cells/extremely low or no expression). The proportion of nonobstructive azoospermia men with an abnormal expression pattern of claudin-11, particularly that of Sertoli cell-only syndrome men, was significantly greater than that of obstructive azoospermia men. Furthermore, claudin-11 expression showing an abnormal pattern in men without successful sperm retrieval was significantly frequent compared with those whose sperm were successfully retrieved.
  
  
  CONCLUSIONS
  These findings suggest that disorganization of claudin-11 expression in Sertoli cells might be one of the factors involved in the impairment of spermatogenesis.
authors.affiliation: Division of Urology, Department of Surgery Related, Faculty of Medicine, Kobe University Graduate School of Medicine, Kobe, Japan. kchiba@med.kobe-u.ac.jp
authors.forename: Koji
authors.initials: K
authors.lastname: Chiba
authors.forename: Kohei
authors.initials: K
authors.lastname: Yamaguchi
authors.forename: Makoto
authors.initials: M
authors.lastname: Ando
authors.forename: Hideaki
authors.initials: H
authors.lastname: Miyake
authors.forename: Masato
authors.initials: M
authors.lastname: Fujisawa
mesh_terms: D000328:Adult; D053713:Azoospermia / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D001706:Biopsy; D057167:Claudins / Q000096:biosynthesis / Q000235:genetics*; D005786:Gene Expression Regulation; D006801:Humans; D007248:Infertility, Male / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D008297:Male; D008856:Microscopy, Fluorescence; D009845:Oligospermia / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D012333:RNA, Messenger / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012708:Sertoli Cells / Q000378:metabolism* / Q000473:pathology; D013091:Spermatogenesis / Q000235:genetics*; D013094:Spermatozoa / Q000378:metabolism; D013737:Testis / Q000378:metabolism* / Q000473:pathology
chemical_list: C120453:CLDN11 protein, human; D057167:Claudins; D012333:RNA, Messenger