Nav: Home

Not just a stem cell marker

January 22, 2018

A protein used to identify blood-forming cells is much more than a mere surface marker. A KAUST study shows that this protein, known as CD34, also plays a key role in binding adhesion molecules in the bone marrow.

The discovery that this binding aids in the proper engraftment of blood-forming stem and progenitor cells following their transplantation is a result that opens the door to "improving the migration of these cells for therapeutic endeavors," says Jasmeen Merzaban, the biochemist who led the team.

Stem cell transplants are used to treat patients with a variety of life-threatening blood disorders. These stem cells, when derived from an adult (as opposed to from cord blood), are isolated by giving the donor a drug that causes stem cells in the bone marrow to mobilize and enter the bloodstream. The blood is then run through a device that extracts all the cells expressing CD34.

These CD34-positive cells can give rise to all the various types of blood components--but they're not the only ones with this ability. Some cells that don't express this surface marker can do the same; however, CD34-negative cells in circulation aren't as good at finding their way to the bone marrow. Thus, doctors have tended to focus on CD34 selection as an easy and effective means of enriching for high-potential blood stem and progenitor cells despite the longstanding mystery of the normal biological function of CD34.

Merzaban and her colleagues revealed one of the functions of this protein by first testing different populations of blood-forming cells for their ability to bind adhesion molecules. They showed that only those cells expressing CD34 could do so, and an unbiased protein screen revealed that CD34 itself was responsible for this binding. Knocking down the protein confirmed CD34's essential role in cell migration.

According to the study's first author, Dina AbuSamra, a former doctoral student in Merzaban's lab now at Harvard Medical School, the results have therapeutic implications beyond simply understanding transplantation. As she points out, the CD34 protein that's found on the surface of leukemic stem cells is different from the one on healthy blood-forming stem cells. There is potential to exploit this difference "to identify leukemic stem cells and, in theory, target them using various approaches," AbuSamra says.

Merzaban also suggests that CD34-negative blood-forming stem cells--a population currently overlooked in transplantation medicine--could be manipulated in ways that boost their binding abilities. Adding these cells to the CD34-positive population might collectively augment overall efficiencies of the procedure, leading to long-term success following transplants. "This is currently a major focus of our lab," Merzaban says.
-end-


King Abdullah University of Science & Technology (KAUST)

Related Stem Cells Articles:

More selective elimination of leukemia stem cells and blood stem cells
Hematopoietic stem cells from a healthy donor can help patients suffering from acute leukemia.
Computer simulations visualize how DNA is recognized to convert cells into stem cells
Researchers of the Hubrecht Institute (KNAW - The Netherlands) and the Max Planck Institute in Münster (Germany) have revealed how an essential protein helps to activate genomic DNA during the conversion of regular adult human cells into stem cells.
First events in stem cells becoming specialized cells needed for organ development
Cell biologists at the University of Toronto shed light on the very first step stem cells go through to turn into the specialized cells that make up organs.
Surprising research result: All immature cells can develop into stem cells
New sensational study conducted at the University of Copenhagen disproves traditional knowledge of stem cell development.
The development of brain stem cells into new nerve cells and why this can lead to cancer
Stem cells are true Jacks-of-all-trades of our bodies, as they can turn into the many different cell types of all organs.
Healthy blood stem cells have as many DNA mutations as leukemic cells
Researchers from the Princess Máxima Center for Pediatric Oncology have shown that the number of mutations in healthy and leukemic blood stem cells does not differ.
New method grows brain cells from stem cells quickly and efficiently
Researchers at Lund University in Sweden have developed a faster method to generate functional brain cells, called astrocytes, from embryonic stem cells.
NUS researchers confine mature cells to turn them into stem cells
Recent research led by Professor G.V. Shivashankar of the Mechanobiology Institute at the National University of Singapore and the FIRC Institute of Molecular Oncology in Italy, has revealed that mature cells can be reprogrammed into re-deployable stem cells without direct genetic modification -- by confining them to a defined geometric space for an extended period of time.
Researchers develop a new method for turning skin cells into pluripotent stem cells
Researchers at the University of Helsinki, Finland, and Karolinska Institutet, Sweden, have for the first time succeeded in converting human skin cells into pluripotent stem cells by activating the cell's own genes.
In mice, stem cells seem to work in fighting obesity! What about stem cells in humans?
This release aims to summarize the available literature in regard to the effect of Mesenchymal Stem Cells transplantation on obesity and related comorbidities from the animal model.
More Stem Cells News and Stem Cells Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Our Relationship With Water
We need water to live. But with rising seas and so many lacking clean water – water is in crisis and so are we. This hour, TED speakers explore ideas around restoring our relationship with water. Guests on the show include legal scholar Kelsey Leonard, artist LaToya Ruby Frazier, and community organizer Colette Pichon Battle.
Now Playing: Science for the People

#568 Poker Face Psychology
Anyone who's seen pop culture depictions of poker might think statistics and math is the only way to get ahead. But no, there's psychology too. Author Maria Konnikova took her Ph.D. in psychology to the poker table, and turned out to be good. So good, she went pro in poker, and learned all about her own biases on the way. We're talking about her new book "The Biggest Bluff: How I Learned to Pay Attention, Master Myself, and Win".
Now Playing: Radiolab

Uncounted
First things first: our very own Latif Nasser has an exciting new show on Netflix. He talks to Jad about the hidden forces of the world that connect us all. Then, with an eye on the upcoming election, we take a look back: at two pieces from More Perfect Season 3 about Constitutional amendments that determine who gets to vote. Former Radiolab producer Julia Longoria takes us to Washington, D.C. The capital is at the heart of our democracy, but it's not a state, and it wasn't until the 23rd Amendment that its people got the right to vote for president. But that still left DC without full representation in Congress; D.C. sends a "non-voting delegate" to the House. Julia profiles that delegate, Congresswoman Eleanor Holmes Norton, and her unique approach to fighting for power in a virtually powerless role. Second, Radiolab producer Sarah Qari looks at a current fight to lower the US voting age to 16 that harkens back to the fight for the 26th Amendment in the 1960s. Eighteen-year-olds at the time argued that if they were old enough to be drafted to fight in the War, they were old enough to have a voice in our democracy. But what about today, when even younger Americans are finding themselves at the center of national political debates? Does it mean we should lower the voting age even further? This episode was reported and produced by Julia Longoria and Sarah Qari. Check out Latif Nasser's new Netflix show Connected here. Support Radiolab today at Radiolab.org/donate.