Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists develop barcoding tool for stem cells

06.10.2014

New technology that tracks the origin of blood cells challenges scientific dogma

A 7-year-project to develop a barcoding and tracking system for tissue stem cells has revealed previously unrecognized features of normal blood production: New data from Harvard Stem Cell Institute scientists at Boston Children's Hospital suggests, surprisingly, that the billions of blood cells that we produce each day are made not by blood stem cells, but rather their less pluripotent descendants, called progenitor cells.

Barcoded Blood Stem Cells

New genetic barcoding technology allows scientists to identify differences in origin between individual blood cells.

Credit: Camargo Lab

The researchers hypothesize that blood comes from stable populations of different long-lived progenitor cells that are responsible for giving rise to specific blood cell types, while blood stem cells likely act as essential reserves.

The work, supported by a National Institutes of Health Director's New Innovator Award and published in Nature, suggests that progenitor cells could potentially be just as valuable as blood stem cells for blood regeneration therapies.

This new research challenges what textbooks have long read: That blood stem cells maintain the day-to-day renewal of blood, a conclusion drawn from their importance in re-establishing blood cell populations after bone marrow transplants—a fact that still remains true. But because of a lack of tools to study how blood forms in a normal context, nobody had been able to track the origin of blood cells without doing a transplant.

Boston Children's Hospital scientist Fernando Camargo, PhD, and his postdoctoral fellow Jianlong Sun, PhD, addressed this problem with a tool that generates a unique barcode in the DNA of all blood stem cells and their progenitor cells in a mouse.

When a tagged cell divides, all of its descendant cells possess the same barcode. This biological inventory system makes it possible to determine the number of stem cells/progenitors being used to make blood and how long they live, as well as answer fundamental questions about where individual blood cells come from.

"There's never been such a robust experimental method that could allow people to look at lineage relationships between mature cell types in the body without doing transplantation," Sun said. "One of the major directions we can now go is to revisit the entire blood cell hierarchy and see how the current knowledge holds true when we use this internal labeling system."

"People have tried using viruses to tag blood cells in the past, but the cells needed to be taken out of the body, infected, and re-transplanted, which raised a number of issues," said Camargo, who is a member of Children's Stem Cell Program and an associate professor in Harvard University's Department of Stem Cell and Regenerative Biology. "I wanted to figure out a way to label blood cells inside of the body, and the best idea I had was to use mobile genetic elements called transposons."

A transposon is a piece of genetic code that can jump to a random point in DNA when exposed to an enzyme called transposase. Camargo's approach works using transgenic mice that possess a single fish-derived transposon in all of their blood cells. When one of these mice is exposed to transposase, each of its blood cells' transposons changes location. The location in the DNA where a transposon moves acts as an individual cell's barcode, so that if the mouse's blood is taken a few months later, any cells with the same transposon location can be linked back to its parent cell.

The transposon barcode system took Camargo and Sun seven years to develop, and was one of Camargo's first projects when he opened his own lab at the Whitehead Institute for Biomedical Research directly out of grad school. Sun joined the project after three years of setbacks, and accomplished an experimental tour de force to reach the conclusions in the Nature paper, which includes data on how many stem cells or progenitor cells contribute to the formation of immune cells in mouse blood.

With the original question of how blood arises in a non-transplant context answered, the researchers are now planning to explore many more applications for their barcode tool.

"We are also tremendously excited to use this tool to barcode and track descendants of different stem cells or progenitor cells for a range of conditions, from aging, to the normal immune response," Sun said. "We first used this technology for blood analysis, however, this system can also help address basic questions about cell populations in solid tissue. You can imagine being able to look at tumor progression or identify the precise origins of cancer cells that have broken off from a tumor and are now circulating in the blood."

"I think that not only for the blood field, this can change the way people look at stem cell and progenitor relationships," Camargo added. "The feedback that we have received from other experts in the field has been fantastic. This can truly be a groundbreaking technology."

###

This research was supported by an NIH Director's New Innovator Award (DP2OD006472) and the Harvard Stem Cell Institute.

Cited: Sun, J, et. al., Clonal dynamics of native haematopoiesis. Nature. October 16, 2014. DOI: 10.1038/nature13824

Joseph Caputo | Eurek Alert!
Further information:
http://www.harvard.edu/

More articles from Life Sciences:

nachricht Scientists uncover the role of a protein in production & survival of myelin-forming cells
19.07.2018 | Advanced Science Research Center, GC/CUNY

nachricht NYSCF researchers develop novel bioengineering technique for personalized bone grafts
18.07.2018 | New York Stem Cell Foundation

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Future electronic components to be printed like newspapers

A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.

The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

A smart safe rechargeable zinc ion battery based on sol-gel transition electrolytes

20.07.2018 | Power and Electrical Engineering

Reversing cause and effect is no trouble for quantum computers

20.07.2018 | Information Technology

Princeton-UPenn research team finds physics treasure hidden in a wallpaper pattern

20.07.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>