Comparative study between slow freezing and vitrification of mouse embryos using different cryoprotectants

Area of Science:

• Reproductive Biology
• Cryobiology
• Developmental Biology

Background:

• Cryopreservation is crucial for preserving reproductive potential.
• Optimizing cryoprotectants and protocols is essential for successful embryo development post-thaw.

Purpose of the Study:

• To evaluate the efficacy of different cryoprotectants (propylene glycerol, ethylene glycol, DMSO, glycerol) and protocols (slow-freezing, Vit-Master vitrification) on mouse eight-cell embryo development.
• To determine the optimal cryoprotectant for each specific cryopreservation method.

Main Methods:

• Mouse eight-cell embryos were cryopreserved using slow-freezing or Vit-Master vitrification with four cryoprotectants: PROH, EG, DMSO, and G.
• Post-thaw assessment included survival rate, blastocyst formation rate, and hatching rate.

Main Results:

• For slow-freezing, PROH yielded significantly higher survival, blastocyst formation, and hatching rates compared to DMSO and G.
• For Vit-Master vitrification, EG demonstrated significantly superior outcomes in all assessed parameters compared to PROH, DMSO, and G.
• No significant differences were observed among DMSO, G, and EG for slow-freezing, nor among PROH, DMSO, and G for vitrification.

Conclusions:

• Propylene glycerol is the optimal cryoprotectant for cryopreserving mouse eight-cell embryos using the slow-freezing method.
• Ethylene glycol is the optimal cryoprotectant for cryopreserving mouse eight-cell embryos using the Vit-Master vitrification protocol.
• These findings offer valuable insights for clinical and laboratory applications in assisted reproduction.