Sperm cryopreservation with empty human or mouse zona pellucidae. A comparison.

Area of Science:

• Reproductive biology
• Cryopreservation techniques
• Spermatozoa research

Background:

• Sperm cryopreservation is crucial for assisted reproductive technologies.
• Severe oligoasthenozoospermia presents challenges for successful sperm storage and utilization.
• The zona pellucida (ZP) of oocytes has been explored as a potential vehicle for sperm cryopreservation.

Purpose of the Study:

• To evaluate the efficacy of empty zona pellucidae (ZP) from human and mouse oocytes for cryopreserving spermatozoa.
• To compare the performance of human ZP versus mouse ZP in sperm cryopreservation for patients with severe oligoasthenozoospermia.

Main Methods:

• Empty ZP were created by removing the cytoplasm from human or mouse oocytes.
• Spermatozoa from patients with severe oligoasthenozoospermia were injected into the empty ZP.
• Following a freeze-thaw cycle, sperm parameters including number, motility, loss, and recovery rate were assessed and compared between human and mouse ZP groups.

Main Results:

• No significant differences were observed in the number of spermatozoa per ZP, motile sperm count before freezing, or post-thaw motility between human and mouse ZP groups.
• The mean sperm recovery rate was approximately 80%, with a mean loss of 1.6% after thawing.
• Overall sperm parameters, including pre-freeze and post-thaw motility, were comparable across all experimental groups.

Conclusions:

• Empty zona pellucidae (ZP) serve as an ideal vehicle for the cryopreservation of sperm from individuals with severe oligoasthenozoospermia.
• There were no statistically significant differences in sperm cryopreservation efficacy between human and mouse ZP.