Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Carnegie Mellon Scientists Track Neuronal Stem Cells Using MRI

30.09.2011
Patented MRI Reporter Technology Could Inform Treatment for Brain Injury and Neurological Disease

Carnegie Mellon University biologists have developed an MRI-based technique that allows researchers to non-invasively follow neural stem cells in vivo.

The recently patented technology could be used to further the study of neural stem cells and inform the development of new treatments for brain injury caused by trauma, stroke, Parkinson’s disease and other neurological disorders. The findings, authored by Associate Professor of Biological Sciences Eric Ahrens and Biological Sciences postdoctoral student Bistra Iordanova, are published online in the journal NeuroImage.

Legend had it that once a brain cell dies, it’s lost forever. Neuroscientists now know that this is purely myth, having proved that the brain is constantly producing new neurons. These neural stem cells are born deep in an area of the brain called the subventricular zone. As time goes on, the cells, also called neuroblasts, make their way to other areas of the brain where they mature into functioning neurons. The brain’s ability to regenerate its cells is of great interest to scientists.

“If we could better understand the molecular migratory signals that guide neuroblasts, we could try to redirect these cells to areas of the brain harmed by stroke or traumatic brain injury. With this information, scientists might be able to one day repair the brain,” said Ahrens, who also is a member of the Pittsburgh NMR Center for Biomedical Research.

Studying cells in a living brain is problematic. Common forms of in vivo cell imaging like fluorescence and bioluminescence rely on light to produce images, making them unsuitable for viewing neuroblasts buried deep beneath the skull and layers of opaque tissue. Until now, scientists had only been able to study neuronal stem cells by looking at slices of the brain under a microscope. Ahrens was able to surmount this problem using MRI technology.

Rather than light, MRI uses magnets to create high-resolution images. A typical MRI scan uses a magnetic field and radio frequency pulses to cause the hydrogen protons found in the body’s water molecules to give off signals. Those signals are converted into a high-resolution image.

At the foundation of this work is a technology Ahrens developed. As reported in a 2005 issue of Nature Medicine, Ahrens developed a method that causes cells to produce their own contrast agent allowing them to be imaged with MRI. Using a viral vector, Ahrens incorporated the gene that produces the naturally occurring metalloprotein ferritin into living cells. Ferritin, which is present in all biological cells, harvests and stores naturally occurring iron. When the cells tagged with ferritin began to produce increased amounts of the protein, they draw in additional iron, turning themselves into nanomagnets. This disrupts the magnetic field surrounding the tagged cells, changing the signal given off by adjacent water molecules. This change appears as dark spots on the MRI image indicating the cells' presence. Since then, Ahrens’ team has improved on the process, developing an engineered form of ferritin that is a more effective MRI reporter than naturally occurring ferritin.

In the current study, Iordanova and Ahrens used the same technique as in the initial study, this time tagging neuroblasts with the engineered ferritin. They incorporated the DNA sequence for the engineered metalloprotein into an adenovirus vector, which they then injected into the subventricular zone of a rat brain. The adenovirus infected the neural stem cells giving the cells the genetic instructions to begin producing the ferritin reporter. Iordanova then imaged the brain with MRI and found that she was able to follow — in real time — the neuroblasts as they traveled toward the olfactory bulb and ultimately formed new inhibitory neurons. These results mirrored what had been observed in histology studies.

Recently, Carnegie Mellon received a patent for the reporter. Ahrens hopes to continue to develop the technology in order to allow researchers to better understand neuronal stem cells and how neurons regenerate. Ahrens also plans to use the reporters to improve clinical trials of cell-based therapies. By incorporating the reporter into the cells before implantation, researchers would be able to find the answer to a number of critical questions.

“Where do these cells go, days, weeks and months later? How do we know that they’ve grafted to the right cells? Or have they grafted in the wrong place? Or died?” Ahrens asked. “The reporter can show us the answers.”

The National Science Foundation and National Institutes of Health funded this research.

About Carnegie Mellon: Carnegie Mellon (www.cmu.edu) is a private, internationally ranked research university with programs in areas ranging from science, technology and business, to public policy, the humanities and the fine arts. More than 11,000 students in the university’s seven schools and colleges benefit from a small student-to-faculty ratio and an education characterized by its focus on creating and implementing solutions for real problems, interdisciplinary collaboration and innovation. A global university, Carnegie Mellon’s main campus in the United States is in Pittsburgh, Pa. It has campuses in California’s Silicon Valley and Qatar, and programs in Asia, Australia, Europe and Mexico. The university is in the midst of a $1 billion fundraising campaign, titled “Inspire Innovation: The Campaign for Carnegie Mellon University,” which aims to build its endowment, support faculty, students and innovative research, and enhance the physical campus with equipment and facility improvements.

By: Jocelyn Duffy, jhduffy@andrew.cmu.edu, 412-268-9982

Jocelyn Duffy | EurekAlert!
Further information:
http://www.cmu.edu
http://www.cmu.edu/mcs/news/pressreleases/2011/09_27_NeuroblastReporter.html

More articles from Life Sciences:

nachricht A novel socio-ecological approach helps identifying suitable wolf habitats
17.02.2017 | Universität Zürich

nachricht New, ultra-flexible probes form reliable, scar-free integration with the brain
16.02.2017 | University of Texas at Austin

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Switched-on DNA

20.02.2017 | Materials Sciences

Second cause of hidden hearing loss identified

20.02.2017 | Health and Medicine

Prospect for more effective treatment of nerve pain

20.02.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>