Dr. Crystal Ruff is a keen investigator in the field of regenerative neuroscience and translational health research, with a proven track record of academic and performance excellence.
In this TEDx Talk Dr. Crystal explains what stem cells are and how they are changing the way we treat diseases.
Below is the full text of her presentation at TEDxLondonBusinessSchool.
For the past 12 years, I have been a researcher in the field of regenerative medicine. As a doctor of neuroscience, my work investigates whether or not we can use stem cells to help children who have had brain injury or adults with spinal cord injury.
Today, I am going to speak with you about how we are changing the future with stem cells.
I believe that stem cells are the new Internet. Think about it. Think about how the Internet completely changed the way that we communicate, the way that we do business, and even the way that we gather data and information.
Similarly, I believe that stem cells have the power to revolutionize the whole concept of healthcare.
So to start, let’s have a little audience participation. Put your hand up: how many of you have heard of the term “stem cells”?
Now leave your hand up if you can tell me what they are. This illustrates a very important part of my work in science communications.
Most of us have heard of the term stem cells either through the media or through our friends, but very few of us actually know what they are, what they can do, and, importantly, what they can’t do.
So, today, we’re going to speak a little about what stem cells are, we’re going to look at what they’re currently being used for, and where the future of the field lies.
So, you can’t be expected to understand about stem cell treatments if you don’t understand what stem cells are to begin with. This is something that I like to call “Stem Cells: 101.”
We all know that the hundreds of cells in the human body all originate from one fertilized egg. If you think of this as a ball rolling down a hill: at the top of the hill, the ball can go to any number of destinations downhill, but as it rolls down guided by gravity, it hits a series of forks in the road. After which it must make a decision to go one way or the other, and that restricts its potential outcomes.
Similarly, stem cells during the process of differentiation face a series of fate decisions where they must choose which cell type to specialize into, and they cannot go back. Near the top of the hill, you see pluripotent stem cells: “pluri-” meaning “many”; “potent”, “potencies.”
Embryonic pluripotent stem cells are the type of stem cell that people most often associate with the word. However, in reality, these cells are virtually never used in transplant paradigms. Instead, we differentiate the cell down into multipotent progenitors that are very specialized for the type of tissue that we want to get.
It’s important to note that one type of multipotent cell cannot make adult cells of another type. For example, fat stem cells cannot make cells of the brain or the eye, and vice versa.
So, you might ask, if pluripotent stem cells can turn into any cell in the body, why don’t we just inject those? You know, they could go to the site, they could travel to the site of whatever is injured and turn into the cells that we need. Right? Wrong!
Because they could turn into something like this. This is called a teratoma. The problem is once we put stem cells in, we cannot control where they go or what cells they turn into. They could turn into all of the cells in the body all at once, all in the same place.
Here you can see hair, fat, tooth, gut, bone – imagine if this were in your brain or your eye. This is why we must differentiate cells into the specific progenitors as much as possible before we’re thinking of transplanting them in.
Now, all of our adult tissue has its own multipotent cells within it, that’s what helps us to grow or when we’re repairing injury, and these can be harvested in many tissues, and grown in the lab for transplanting paradigms.
However, there are some tissues that you can’t harvest. Think about the brain or the heart or the eye. Going in there to get cells could kill you. So we have to think of other alternative cell sources for these cells. And this is where pluripotent cells come in.
Now, up until now, embryonic drive cells have been differentiated down the hill into the stem cell types that we need. Recently, induced pluripotent stem cells were developed where you can take adult skin samples, your own consenting adult, push them back up the hill using four chemical factors, and then differentiate them down to the cell type you need. This was discovered recently by Shinya Yamanaka, who went on to win the Nobel Prize.
The good thing about this is it uses non-embryonic sources, and it’s your own tissue, so your body is not likely to reject it. Alternatively, direct lineage reprogramming – there we go – takes you from A to B without this intermediate step up the hill.
You can take adult skin samples and differentiate them directly into the cell type you choose using different chemical triggers.