Mouse sperm cryopreservation and recovery using the I·Cryo kit

Area of Science:

• Animal Genetics
• Reproductive Biology
• Cryobiology

Background:

• Genetically modified (GM) mouse strains are crucial research tools, but often lack backup preservation methods.
• Embryo cryopreservation is effective but costly and resource-intensive.
• Sperm cryopreservation offers a more cost-effective alternative for archiving mouse strains.

Purpose of the Study:

• To evaluate a newly developed I•Cryo kit for mouse sperm cryopreservation.
• To assess the efficacy of the I•Cryo kit compared to a basic cryoprotective agent (CPA).
• To demonstrate the utility of the I•Cryo kit for archiving and recovering GM mouse lines.

Main Methods:

• Sperm from five inbred mouse strains were cryopreserved using the I•Cryo kit and a basic CPA.
• Sperm motility and progressive motility were assessed post-thaw.
• In vitro fertilization (IVF) was performed using recovered sperm to assess embryo development.
• The I•Cryo kit was used to archive 49 GM mouse lines over 1.5 years.

Main Results:

• The I•Cryo kit significantly improved sperm motility (> 60%) and rapid progressive motility (> 45%) compared to the basic CPA across five mouse strains.
• Two-cell stage embryo development after IVF with recovered sperm was consistently improved in all tested strains.
• Successful archiving and recovery of 49 GM mouse lines were achieved using the I•Cryo kit.

Conclusions:

• The I•Cryo kit provides superior cryoprotection for mouse sperm compared to basic CPA.
• This kit enhances sperm quality and subsequent embryo development after IVF.
• The I•Cryo kit is a highly effective and cost-efficient solution for archiving valuable GM mouse strains.