Everyone remembers Dolly, right? That lovable little ball of wool we like to call the first mammalian clone? Come on, of course you do. She was like Anna Nicole Smith after the weight loss, posing on the covers of magazines and newspapers for the world to see in all her glory. A glory, by the way, that ended in a premature death from complications not normally found in sheep.
You might be wondering what went wron—hy it is that this hoofed hottie seemed to fall off the media radar screen once she survived the first few days of her fated existence? To be honest, the answer would take longer than the space I have in this column, but what I will tell you are some things you might want to know about stem cells and cloning before entering the voting booth in November (in case, for some reason, you were still undecided about which hole to punch out).
So let’s start at the beginning, the moment of conception when sperm meets egg and the magic begins. Well, the magic AFTER the magic, that is. A few days post-shagging we have what’s called a blastocyst, a small group of about 30 cells that will give rise to all the highly specialized cells needed to make an adult organism. Pretty convincing cells, wouldn’t you say?
These commanding officers are what scientists call “embryonic stem cells.” You may have heard the term before, but if not then you’re about to be schooled in one of the most controversial topics to hit the US since the “creamy vs. crunchy” debate took elementary school kids by storm in the mid 1930s.
Here’s the deal with embryonic stem cells- they’re important because they are capable of dividing and renewing themselves for long periods of time. Unlike muscle, blood cells or nerve cells, stem cells can proliferate (reproduce, if you will) and produce millions of progeny cells within a few months. What really makes them special is that in addition to proliferating, they have the capacity to differentiate into many different cell types; they’re the utility infielders of the embryo, so to speak.
Two weeks ago, a team of scientists from South Korea successfully cloned a human embryo and extracted stem cells from it. They cloned a human?! Theoretically yes, but actually, this had already been done. What the Koreans did, however, was allow the cells to divide enough times (to the blastocyst stage) so that they were able to remove the stem cells and start new lines separate from the clone. Believe me, this was big.
Biology professor Laura Grabel is working with embryonic stem cells here at Wesleyan. She and the members of her lab study, among other things, neurogenesi—he building of neurons. Using mouse embryonic stem cells, Professor Grabel’s group, in collaboration with Professor Jan Naegele’s lab, has been performing some actual transplant studies. What she does is transplant embryonic stem cell-derived neural progenitors (in English, stem cells for nerves which are grown in the lab) into mice whose brains have been injured. They are trying to get these cells to survive and “on a good day, even look like neurons,” she told me.
Professor Grabel is looking to see if the transplanted cells will take up residence in the brain and therefore replace the damaged tissue. She can tell if this is happening by looking for fluorescent markers found only in the transplanted cells, an easy way of distinguishing the host from the guest. If the cells are bright green, growing and spreading like the beginnings of a neuron, the transplant is working.
So what does all this mean? Who cares if these neural progentor-thingys can survive in a mouse’s brain? What it means is that some day, scientists might be able to treat Alzheimer’s or Parkinson’s disease with cells derived from the patient’s own body. It means that scientists might be able to take the nucleus from one of your skin cells, fuse it with an egg cell whose nucleus has been removed, treat it with chemicals and cause it to make heart cells which could be transplanted to repair your damaged ticker.
If any of this sounds confusing or unbelievable, what you need to know is thi—hile the South Korean scientists achieved something very important, it doesn’t mean that an identical clone is going to be taking your midterms anytime soon. There is a very important distinction between reproductive cloning and therapeutic cloning. The first is what produced Dolly. The second, however, is what Professor Grabel and the South Koreans are hoping their research will eventually lead t—reatments.
“I was there when the Korean scientists talked about their work, and they were very clear that they never had any intention of taking the cells past the blastula stage and that their only goal was to make stem cells,” said Grabel.
When asked what she hoped people knew about stem cell research, Grabel continued, saying “I’d like people to understand the way that our hands our tied in terms of work on human embryonic stem cell lines. There are less than a dozen cell lines left that have been ok’d by Bush that can be studied using federal funds. Most good science is done in academic institutions, funded by federal money.”
Without the graduate programs and commitment from the young scientists who are attracted to Wesleyan, research such as Professor Grabel’s wouldn’t be possible. But like Professor Grabel told me, our current situation isn’t nearly good enough (Thanks GWB, thanks a lot). “Our goal is ultimately to understand how these cells differentiate, not to make a profit. My hope for the future is to generate new stem cells lines because each cell line has its own quirks, and there is no way that we can use the dozen lines available now to do all the things we want to do.” So this November, vote your hear—iterally.
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