Vitrification of biopsied mouse embryos

Area of Science:

• Reproductive Biology
• Cryobiology
• Embryology

Background:

• Cryopreservation is vital for preserving embryos in reproductive research.
• Biopsying embryos for genetic analysis can impact their viability.
• Comparing different vitrification methods is essential for optimizing embryo survival.

Purpose of the Study:

• To compare the efficacy of solid surface vitrification (SSV) against in-straw vitrification for cryopreserving biopsied mouse embryos.
• To evaluate the impact of cryopreservation on the survival and subsequent development of biopsied embryos.
• To determine the optimal vitrification method for morula and blastocyst stage embryos.

Main Methods:

• Eight-cell stage mouse embryos underwent zona drilling and blastomere removal.
• Developed morulae or blastocysts were vitrified using either SSV or in-straw methods with specific cryoprotective agents.
• Embryos were cultured in vitro or transferred to recipient mice post-warming.

Main Results:

• Cryosurvival of biopsied morulae was significantly lower with in-straw vitrification compared to SSV.
• Post-warm development was delayed in both biopsied and non-biopsied morulae and blastocysts, regardless of the vitrification method.
• No significant difference in birth rates was observed between SSV and in-straw methods for non-biopsied embryos, but in-straw vitrified biopsied embryos had a lower birth rate.

Conclusions:

• Solid surface vitrification (SSV) is an effective cryopreservation protocol for biopsied morula and blastocyst stage mouse embryos.
• SSV demonstrates superior cryosurvival rates for biopsied embryos compared to in-straw vitrification.
• While cryopreservation can delay embryonic development, SSV offers a promising method for preserving embryo integrity post-biopsy.