Blastocyst development after assisted reproduction using spermatozoa obtained after testicular stem cell transplantation in mice

BACKGROUND: Since its introduction in 1994, testicular stemcell transplantation (TSCT) has been widely used for research.This technique may also become important for preserving fertilityin pre-pubertal cancer patients. Therefore, it is necessaryto investigate the safety aspects of reproduction using spermatozoaobtained after TSCT. In this study, preimplantation developmentof mouse embryos, using spermatozoa obtained after TSCT, wasexamined. METHODS: TSCT-derived spermatozoa were used for IVFand ICSI. Embryos were cultured for five days until they reachedblastocyst stage and were evaluated by differential staining.RESULTS: IVF revealed significantly lower fertilization anddevelopment rates after TSCT-IVF compared to control-IVF. Blastocystsderived from TSCT-IVF had significantly lower inner cell massnumbers (ICMs) and lower ICM/trophectoderm (TE) ratios comparedto control-IVF blastocysts. No differences in fertilizationand development rates were observed between TSCT-ICSI and control-ICSI,and blastocyst quality in the transplanted group was similarto that of the control blastocysts. CONCLUSION: Our study showedthat after TSCT-IVF, fertilization and preimplantation developmentwere disturbed and blastocysts showed reduced ICM and ICM/TEratio. However, after TSCT-ICSI, both fertilization and preimplantationdevelopment were normal and blastocyst formation was comparableto control-ICSI.