New Sperm Cryopreservation Milestone:
1,000 Strains Cryopreserved and Successfully Recovered
JAX® NOTES Issue 508, Winter 2008
Last year, we announced that, in a joint effort, our Reproductive Sciences and Technology, Evaluation, and Development groups had developed a fast, low-cost, and high-throughput technique for cryopreserving and recovering sperm from genetically engineered mice (JAX® NOTES 2006). The technique, initially used to cryopreserve mouse strains for our own scientists and Repository, is currently being offered to the wider scientific community through JAX® Services.
Since the development of the technique, over 1,000 different mouse strains on 36 genetically defined backgrounds (70% on a C57BL/6J background) have been cryopreserved as sperm, yielding a mean fertilization rate to 2-cell embryos of 49% and a mean recovery to live-born rate of 38%. In a comparison among genetically modified mice on 12 popular backgrounds, our scientists found that fertilization rates achieved with sperm cryopreserved by the new technique were much higher than those achieved with traditionally cryopreserved sperm (Fig. 1). On C57BL/6J and BALB/cByJ backgrounds, they were 6 and 4 times higher respectively, and, on 10 of the 12 backgrounds, they were equivalant to those achieved with freshly collected sperm. Only on 2 strains were they slightly lower than those achieved with freshly collected sperm.
The technique is allowing researchers to manage their mouse colonies more efficiently. Small inactive colonies can be cryopreserved and quickly recovered and expanded when needed. The technique is also a cost-effective disaster recovery method that allows investigators to safeguard their investment of time and money when working with unique strains of mice.
For more information about this service, visit our Web site or contact JAX® Services at 1-800-422-6423 or 1-207-288-5845, or e-mail jaxservices@jax.org.
Figure 1. A comparison of the fertilization rates to 2-cell embryos achieved by 3 types of sperm (frozen by the traditional technique, frozen by the new technique, non-frozen freshly collected sperm) from genetically modified mice on 12 popular backgrounds. Fertilization rates achieved with sperm cryopreserved by the new technique were far greater than those achieved with traditionally cryopreserved sperm. For 10 of the 12 strains, fertilization rates were comparable to those achieved by fresh sperm.
Reference
JAX® NOTES. 2006. Reliable new sperm cryopreservation service developed at The Jackson Laboratory. JAX® NOTES 504:1-2.
Cryopreservation Teams Now Can Come to You!
We can now deploy teams of reproductive specialists to your facility to cryopreserve large numbers of strains. This novel approach is the latest innovation of our Sperm Cryopreservation Service. It is ideally suited for institutions or investigators with large rederivation projects or substantial backlogs of strains that need to be cryopreserved (see case study below). Cryopreservation at your site eliminates shipping costs and minimizes your project management time. Our cryopreservation teams can routinely cryopreserve 120 strains or more on site in a week. After they are cryopreserved, the strains are taken to our Bar Harbor facility for quality control checks and storage. Strains requiring rederivation are recovered by in vitro fertilization and returned to you. Operational savings incurred by The Jackson Laboratory are passed on to you.
For more information, contact JAX® Services at 1-800-422-6423 or 1-207-288-5845, or e-mail jaxservices@jax.org.
On-Site Cryopreservation Case Study
As Peter Mombaerts MD PhD of The Rockefeller University in New York was preparing to move to the Max Planck Institute of Biophysics in Frankfurt, Germany, he needed an efficient way to cryopreserve his strains and move his colonies to his new laboratory. During a week in January 2007, we successfully cryopreserved 127 strains at The Rockefeller University for him. These strains were successfully recovered, and Dr. Mombaerts received rederived mice to rebuild his colonies in his new laboratory. Additionally, to cost-effectively make his published strains available to the research community, Dr. Mombaerts chose to have them distributed by The Jackson Laboratory's Repository. Read Dr. Mombaerts' description of this project.
