Today was something a bit different, and super cool. I spent the entire day with the Assisted Reproductive Technologies lab, observing the fascinated and very important work that they do. They are responsible for rederivation work to supply all of the vivaria with specific pathogen free mice. They do this by using embryo transfer. This site has a good explanation of the process. The microscope used to collect and wash the embryos has a camera attached to it that then feeds into a television. So I got to watch as one of the two women that run the entire program took uteri and flushed them out to collect 2-8 cell embryos to use for transfer. She then collected them with a pipette and washed them repeatedly. When they were ready, a recipient mouse was anesthetized, shaved, scrubbed, and moved to a platform under another microscope. Then the tech did microsurgery – she made an incision in the mouse’s side, found and isolated the reproductive tract, located the infundibulum, and then implanted the embryos. She let me look under the microscope occasionally, and explained everything she was doing and pointed out specific structures. It was so amazing!! It’s such delicate work, and these women are expert at it. After the embryos were transferred, the incision was closed with wound clips and the mouse recovered quickly and without complications. I watched her flush several uteri and do embryo transfer into four mice. I also watched them take cryopreserved embryos from liquid nitrogen, wash them, and implant them into mice. That’s great because if a PI wants to maintain a specific strain but doesn’t currently have a need for the mice, the embryos can be frozen and it eliminates needlessly keeping mice around just for breeding and keeping the strain going. Then in the future if a PI wants to work with the strain, the embryos are removed from the liquid nitrogen and transferred into a recipient mouse. Pretty freaking amazing.
It was really fascinating, and I’m so glad I got the opportunity to hang out with them for a day and experience what they do. There’s obviously a lot more to it than I typed here, but you get the basic idea.