Hello SITN members! Please pardon the brief hiatus in our email newsletter. We have been busy choosing exciting topics and recruiting great speakers for this fall's series. Please keep an eye on our website or await official announcement our season's topics and schedule in the August Newsflash! Remember, lectures begin September 8th, 2005!
If you have been keeping up with your science in the news you'll realize that the end of May brought some interesting announcements about stem cell research. So if you've been holding you breath waiting for our take on the science involved to be covered in our next SITNewsflash, wait no longer... (And if you’ve been welling up with questions since those announcements, remember that you can post them to our Question and Answer site at http://sitn.hms.harvard.edu/qanda/ -- keep the great questions coming!)
Embryonic Stem Cells in the News
The study of embryonic stem cells (ES cells) continues to be a controversial story both politically and scientifically. Four years ago, the federal government restricted the granting of federal research funding for work on embryonic stem cells. Recently, Illinois announced itself as the fourth state to set aside funding specifically for research on ES cells, joining California, New Jersey, and Connecticut. While each state’s plan differs slightly, they all have been motivated in part by the potential of ES cells to yield breakthrough treatments for debilitating diseases and conditions such as spinal cord injury and Alzheimer’s disease. However, even though human ES cells have the ability to form any cell or tissue type, they can only be harvested from unwanted or discarded embryos, leading some to wonder if the promise of embryonic stem cells comes at too great a price. Furthermore, their clinical utility has not yet been proven. However, recent studies from a group of Korean scientists may be expanding the future ability of researchers to apply ES cell research in a clinical setting.
The current procedure used to clone cells, known as nuclear transfer, involves taking an egg cell and replacing its nucleus with a nucleus from a donor cell. Then the egg is tricked into developing as if it had been normally fertilized (by a sperm, not a scientist) resulting in a new embryo which is genetically identical to the original donor cell. This procedure has been used over the years to “clone” a wide variety of species (remember Dolly the sheep?), but was thought to be too inefficient to be used with human cells. The Korean group was able to modify the normal nuclear transfer procedure with human egg cells to efficiently create ES cells from the resulting embryo. In addition to modifications to the technique used for the nuclear transfer, the Korean group decided to start with egg cells which were donated by healthy young women. This combination resulted in many successfully cloned ES cells from fewer starting egg cells, a huge improvement in efficiency. Excitingly, these ES cells had the same genetic make-up as the donor nucleus from which they were made, demonstrating that ES cells unique to an individual can be generated in a lab. In the future these “patient-specific” cells might reduce the potential for immune system rejection in the treated patient.
This finding, while exciting, also carries with it an additional ethical dilemma. In the past, eggs for nuclear transfer had been collected from older, relatively infertile women who were receiving fertility drugs. In order to achieve efficient success, the scientists in this Korean study collected eggs cells from young, fertile women who agreed to donate them. This may present a situation in the future where some fear that young women may be encouraged to donate their eggs at risk to themselves. Even still, this new finding is sure to reopen discussion on the future potential of stem cell research.
