Reproductive capacity of sperm obtained after germ cell transplantation in a mouse model.
BACKGROUND
The testicular stem cell transplantation technique has become an established research model in the mouse. This technique may also become useful for clinical applications. Therefore, it is necessary to investigate whether sperm obtained after testicular stem cell transplantation retain their full functional capacity and whether they are able to produce normally-developing embryos. This study aimed at evaluating the fertilizing and developmental abilities of sperm obtained after stem cell transplantation.


METHODS
First, transplanted male mice were mated with females in order to evaluate in-vivo conception. Subsequently, functionality of sperm obtained after testicular germ cell transplantation was investigated by performing both IVF and ICSI.


RESULTS
After in-vivo conception we found that in the control group 90% of the mice with a copulating plug became pregnant. In the experimental group only 35% of the mice with a copulating plug became pregnant (P = 0.006). After IVF, fertilization and blastocyst developmental rates were significantly lower in the transplanted group (P < 0.0001). Fertilization and blastocyst developmental rates after ICSI were comparable with control sperm.


CONCLUSIONS
Our study showed that in the mouse, sperm obtained after stem cell transplantation are able to fertilize oocytes on the basis of assisted reproduction. It is recommended to further investigate this method in the human, as well as to investigate the post-implantation development of the embryo.
Goossens
E
E
Research Centre for Reproduction and Genetics, Faculty of Medicine and Pharmacy, Dutch-speaking Brussels Free University, Laarbeeklaan 101, 1090 Brussels, Belgium. ellen.goossens@az.vub.ac.be
Frederickx
V
V
De Block
G
G
Van Steirteghem
A C
AC
Tournaye
H
H
D000818:Animals; D001755:Blastocyst / Q000502:physiology; D002678:Chimera; D005314:Embryonic and Fetal Development; D005260:Female; D005306:Fertilization; D005307:Fertilization in Vitro; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D011247:Pregnancy; D018873:Pregnancy Rate; D020554:Sperm Injections, Intracytoplasmic; D013094:Spermatozoa / Q000502:physiology*; D033581:Stem Cell Transplantation; D013737:Testis; D014019:Tissue Donors