title: Male Pronuclear Formation using Dog Sperm Derived from Ectopic Testicular Xenografts, Testis, and Epididymis.
abstract: BACKGROUND
  Testis tissue xenografting and the resultant sperm in a xenograft may provide a unique approach to rescue the genetic material of males that die prematurely and is a model for the study of human spermatogenesis and can represent an alternative approach for fertility preservation in cancer patients. This study was aimed to evaluate the xenogenic dog sperm in formation of male pronucleus following injection into the sheep oocytes.
  
  
  METHODS
  The in vitro matured slaughterhouse derived sheep oocytes were subjected to Intracytoplasmic Sperm Injection (ICSI) with epididymal, testicular, and xenogenic dog sperm. The ICSI was performed after scoring of the sperm midpiece using an IX71-Olympus inverted microscope with Nomarsky optics. Within 1 hr after injection, the injected oocytes in activated group were exposed to 5 µM ionomycin for 5 min. The data were analyzed by Chi-square and ANOVA using SigmaStat, version 3.5, and p<0.05 was considered significant.
  
  
  RESULTS
  The formation of female pronucleus after ICSI of xenogenic sperm was higher than epididymal and testicular sperm in non-activated oocytes. The corresponding rate in activated oocytes was higher or comparable with testicular and epididymal sperm. The rate of male pronucleus formation after ICSI of xenogenic sperm was comparable with injection of two other sperm sources. Oocyte activation had an inductive role in female and male pronuclear formation.
  
  
  CONCLUSIONS
  Dog xenogenic sperm was capable to induce oocyte activation and proportion of male pronucleous formation was comparable to the testicular and epididymal sperm.
authors.affiliation: Reproductive Biotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran ; Department of Gametes and Cloning, Research Institute of Animal Embryo Technology, Shahrekord University, Shahrekord, Iran.
authors.forename: Abolfazl
authors.initials: A
authors.lastname: Shirazi
authors.affiliation: Department of Gametes and Cloning, Research Institute of Animal Embryo Technology, Shahrekord University, Shahrekord, Iran.
authors.forename: Asma
authors.initials: A
authors.lastname: Khadivi
authors.affiliation: Department of Gametes and Cloning, Research Institute of Animal Embryo Technology, Shahrekord University, Shahrekord, Iran.
authors.forename: Naser
authors.initials: N
authors.lastname: Shams-Esfandabadi
keywords: Canine; ICSI; Pronucleus; Xenograft