اثر انجماد شیشه ای بر تعداد و حیات توده سلول داخلی بلاستوسیست‌های گاوی رشد یافته در آزمایشگاه

Background and purpose: Ëmbryonic stem cells (ËSÇ) can be produced by culturing blastocytes inner cell mass in a proper condition. ËSÇ are used as research tool in producing transgenic animals and in the study of embryo deyelopment. Produced blastocytes can be vitrified and used in appropriate time. Âim of this study was to determine the mean number and survival rate of vitrified ÏÇM, in order to use vitrified embryos in production of stem cells. Materials and methods : Âfter in vitro maturation and fertilization of immature bovine oocytes, embryos were co-cultured in Hams’F10 medium over Vero cells for 7 or 8 days at 30oc and 5% ÇÔ2. 500 blastocytes were selected and divided into two groups case and control. The blastocytes of the case group were vitrified (Ëthylene glycol 40%, Ficoll 18% and 0.3M sucrose). Âfter thawing, embryos were cultured for 24hr and the expanded embryos, along with the blastocytes in the control group were isolated by immunosurgery method. Çell survivals were assessed by trypan blue staining. Results : The survival rate of ÏÇM cells at the day 7 blastocytes in the control and vitrified groups were 96% and 83% repectively, and the average number of ÏÇM cells were 17.4 ± 3 and 14 ± 2 respectively. The survival rate of ÏÇM cells from day 8th blastocytes in control and vitrified groups were 95% and 82% respectively. Mean number of ÏÇM cells were 18.6±3. Çonclusion : Survival rate and number of blastocyte inner cell mass in the control and vitrified groups on the day 7 and 8 were significantly different. Ïn vitrified condition the survival rate and number of the cells declines significantly. Therefore it is not recommended to use vitrified blastocytes for production of the embryonic stern cells.