For years researchers have struggled to create human blood stem cells in the lab. They have done it several times with animal models, but the human kind? Well, that’s proved a bit trickier. Now a CIRM-funded team at UC San Diego (UCSD) think they have cracked the code. And that would be great news for anyone who may ever need a bone marrow transplant.
Why are blood stem cells important? Well, they help create our red and white blood cells and platelets, critical elements in carrying oxygen to all our organs and fighting infections. They have also become one of the most important weapons we have to combat deadly diseases like leukemia and lymphoma. Unfortunately, today we depend on finding a perfect or near-perfect match to make bone marrow transplants as safe and effective as possible and without a perfect match many patients miss out. That’s why this news is so exciting.
Researchers at UCSD found that the process of creating new blood stem cells depends on the action of three molecules, not two as was previously thought.
Here’s where it gets a bit complicated but stick with me. The team worked with zebrafish, which use the same method to create blood stem cells as people do but also have the advantage of being translucent, so you can watch what’s going on inside them as it happens. They noticed that a molecule called Wnt9a touches down on a receptor called Fzd9b and brings along with it something called the epidermal growth factor receptor (EGFR). It’s the interaction of these three together that turns a stem cell into a blood cell.
“Previous attempts to develop blood stem cells in a laboratory dish have failed, and that may be in part because they didn’t take the interaction between EGFR and Wnt into account.”
If this new approach helps the team generate blood stem cells in the lab these could be used to create off-the-shelf blood stem cells, instead of bone marrow transplants, to treat people battling leukemia and/or lymphoma.
CIRM is also funding a number of other projects, several in clinical trials, that involve the use of blood stem cells. Those include treatments for: Beta Thalassemia; blood cancer; HIV/AIDS; and Severe Combined Immunodeficiency among others.