title: Regeneration of spermatogenesis by grafting testicular tissue or injecting testicular cells into the testes of sterile mice: a comparative study.
abstract: OBJECTIVE
  To make a comparison between two different approaches-spermatogonial stem cell transplantation and intratesticular grafting, for preservation and reintroduction of spermatogonial stem cells.
  
  
  METHODS
  Prospective experimental study.
  
  
  METHODS
  Academic medical center and teaching hospital.
  
  
  METHODS
  N/A.
  
  
  METHODS
  Intratesticular transplantation, histologic evaluation of testes.
  
  
  METHODS
  Testicular weight, amount of green fluorescence in the testis, and immunostaining for green fluorescent protein.
  
  
  RESULTS
  In a first experiment donor-derived spermatogenesis was found in 65% of the injected testes (41.8 +/- 72.2 mm) compared with 75% of the testes (122.1 +/- 45.6 mm) after tissue grafting. In the second series of experiments complete spermatogenesis was found in 75% of the testes after fresh grafting (93.8 +/- 21.8 mm) compared with 88% after frozen-thawed tissue grafting (84.8 +/- 45.6 mm).
  
  
  CONCLUSIONS
  Both approaches show that spermatogonial stem cells can successfully be introduced to the testis resulting in spermatogenesis. Tissue grafting produced a larger mean donor colony length and there was no significant difference between colonization efficiency using either fresh or frozen-thawed grafts. In a future clinical setting, grafting would be a simple and efficient way for reintroducing stem cells to the testis.
authors.affiliation: Center for Reproductive Medicine and Research Laboratories for Reproductive Medicine, University Hospital and Medical School, Dutch-Speaking Brussels Free University (Vrije Universiteit Brussel), Brussels, Belgium. dorien.van.saen@vub.ac.be
authors.forename: Dorien
authors.initials: D
authors.lastname: Van Saen
authors.forename: Ellen
authors.initials: E
authors.lastname: Goossens
authors.forename: Gert
authors.initials: G
authors.lastname: De Block
authors.forename: Herman
authors.initials: H
authors.lastname: Tournaye
mesh_terms: D000818:Animals; D007248:Infertility, Male / Q000503:physiopathology / Q000601:surgery*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D012038:Regeneration; D012741:Sexual Maturation; D013091:Spermatogenesis / Q000502:physiology*; D013093:Spermatogonia / Q000637:transplantation; D033581:Stem Cell Transplantation / Q000379:methods*; D013737:Testis / Q000637:transplantation; D014184:Transplantation, Homologous