Stem cells, stem cells, stem cells. We hear about these things all the time it seems. Here in California, we ponied up 3 billion
dollars to look into them.
Well, judging by this week's news, it may well be worth the money. There were two big stories about stem cells this week.
The first was using cloned embryos to create personalized stem cells for patients. The second was using stem cells from umbilical cord blood to actually treat a disease. Wow, it was
a big week!
Before discussing these stories in detail, let's make sure we understand what a stem cell is and why they have such potential. If you have a pretty good handle on stem cells already, you can skip this part and start in on the two stories.
Most cells in our body are stuck doing what they do. A liver cell will always be a liver cell; a muscle cell will always be a muscle cell.
And they can't make new copies of themselves. In other words, when they die, they can't replace themselves.
Stem cells are different. Stem cells can keep making more and more of themselves creating an almost endless supply. They can also change into other cells like muscle, nerve, blood or almost anything else.
Where do you find these wonderful cells? The stem cells that can really become any other cell are found only in embryos. Embryos need to be able to make every different kind of cell from a single cell. So these early cells need to be able to become anything.
What makes stem cells controversial is that to get these cells, an embryo must be destroyed. Which is one of the reasons people are looking hard at another type of cell, the adult stem cell.
When a blood cell dies off, where does its replacement come from? Blood stem cells in our bone marrow. Many of our other tissues also have their own supply of adult stem cells.
These stem cells usually can't easily become any other kind of cell. Blood stem cells pretty much turn into different kinds of blood cells in the body. Researchers are working hard to coax them into different kinds of cells but stem cells from embryos are still more versatile.
Where can stem cells be used to treat disease? There are lots of problems that are caused by the loss of some important tissue. Some examples include diabetes, Parkinson's, or spinal cord injuries.
Scientists are trying to use stem cells to recreate the lost cells in these diseases. For example, in diabetes, new pancreatic cells could replace the lost ones. Now instead of treating diabetes with insulin, scientists are hoping to cure it with stem cells.