Dr. Joy Kong explains the two stem cell types used clinically in the U.S.: embryonic stem cells, which can become any cell type but risk forming tumors, and adult stem cells from bone marrow or umbilical cord, which are safer and more metabolically active.
Welcome to episode two of our stem cell series with Dr. Joy Kong. Dr. Kong, what are the major stem cell types that are of clinical relevance.
In the U.S. the major stem cell types will be two the embryonic stem cells versus adult stem cells. So embryonic stem cells are very, very young cells. They're formed at a very early stage of embryo. They're obtained about five to seven days after fertilization. That's when a little ball of cells will be formed, empty ball. And inside of it is what's called inner cell mass. It's among those cells that certain cells can be taken out. That's called an embryonic stem cell. And that has the potential to become any cell in your body. Then we come to adult stem cells. That's either cells from you and me, you know, of our own age, or from a newborn baby. So the birth tissue that comes with a newborn, that's actually adult stem cell, even though we think of them as babies. But when you look at it, you know, from the embryonically speaking, this is very, very much mature cell, the full human has been formed. So because they are further down and they're more mature, they're also limited in what they can become. So even though they're stem ce, but the stem cells have limitations. They can't just become anything you want in your body. What's the advantage of that? The advantage is that it won't go haywire. It has a definite pathway. So it's not going to become anything that any potential that like what embryonic stem cells can lead to. Because that's one of the risks of using embryonic stem cells clinically is because it can become anything, any cells. And that's when it form a cluster of cells of all kinds of tissues. That's what's called a teratoma. And that's the problem. That's a risk associated with stem cell, with embryonic stem cells. And that's why it's not allowed for clinical use yet, because we haven't been able to fully harness control these embryonic stem cells. So adult stem cells, yes, it is allowed for clinical use within certain FDA guidelines. So when we look at adult stem cells, then the two major types will be the birth tissue derived versus people from our own age. So let's talk about cells from our own age. So then the stem cells will be of your age. If you are 20, that's 20 year old stem cells. If you're 40, 60, 80, that's how old those stem cells are. So then you can imagine these cells will have. And if you've gone through all the environmental assaults that your body has gone through, the UV lights, the toxins in environment, the oxidative damages, so the free radicals that's forming that can damage your DNA, so there's more accumulation in DNA, changes in various damages in the cell structure itself, and then also is not as metabolic active, it's just not quite as ready to work. So do they work? Yes, because clinically there has been some success. Of course another benefit of these adult derived stem cells is that they're perfectly matched to yourself. You're giving it to yourself. So that's called autologous transplant. But these cells, the older you get and the sicker you are, that means these cells potentially are sicker as well. And if you carry some kind of condition that has a genetic comp, then those components are also embedded in those stem cells. Whereas if you look at umbilical cord stem cells, of course the origin of the cells matter if it's carefully screened. And the baby comes from very, very healthy family and has perfect prenatal history. Potentially this is a very, very healthy cell. And these cells are a lot more metabolically active, they are more resistant as far as resistant to aging, and they're just more robust, easier to survive. And they also secrete more anti inflammatory factors, they secrete more growth factors to stimulate the local cells to help them to come to work and to regenerate tissue. And also they are more neuroprotective. So there are a lot of benefits that we are finding out that are actually superior in these birth tissue derived stem cells. So the research is very active, things are moving and we're finding out more and more about different types. But these are some kind of the general overview and it's a very exciting field and it's constantly moving. So I look forward to keep sharing information with everyone.
