Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Adult stem cells selectively delivered into the eye and used to control angiogenesis at TSRI

30.07.2002


A team of researchers from The Scripps Research Institute (TSRI) has discovered a way to use adult bone marrow stem cells to form new blood vessels in the eye or to deliver chemicals that will prevent the abnormal formation of new vessels.



This technique, which involves injecting the stem cells into the eye, could potentially be used to stimulate vessel growth and address inherited degenerations of the retina in the first instance, and in the second, to treat ocular diseases resulting from abnormal retinal angiogenesis, the aberrant growth of new blood vessels in the eye, which is the leading cause of vision loss in the United States.

"This is very exciting," says Martin Friedlander, M.D., Ph.D., who led the study. "We have shown that the cells can incorporate into the [degenerating] vasculature and make it normal."


"And when loaded with antiangiogenics, they can selectively wipe out the formation of new blood vessels."

Friedlander, who is Associate Professor in the Department of Cell Biology and Chief of the Retina Service in the Division of Ophthalmology, Department of Surgery at Scripps Clinic, has had a longstanding research program looking at ways of treating eye diseases that result from abnormal angiogenesis.

Abnormal angiogenesis is the cause of visual loss in age-related macular degeneration, where new blood vessels grow under the retina, and diabetic retinopathy, where abnormal vessels grow on top of the retina. The end result is much the same in these diseases--the normal structures for the transmission of light to the back of the eye are lost, and vision is catastrophically impeded in many of the tens of millions of Americans who suffer from them.

From stem cells to vessels

Adult bone marrow stem cells are "pluripotent" which means they have the potential to develop into a number of different cell types, such as red blood cells, platelets, or lymphocytes. The group’s basic technique starts with selecting stem cells from the bone marrow that have the capability of becoming endothelial cells, the major cell type lining blood vessels.

Normally, retinal vascular formation occurs late in human prenatal development, when endothelial cells form a fine mesh of blood vessels in the back of the eye. In diseases like macular degeneration and diabetic retinopathy, aberrant vascular formation occurs later in life.

The vascularization in both diseases involves endothelial cells working in concert with another specialized cell--star-shaped cells called "astrocytes." These astrocytes, when activated, act as a template for vessel formation.

During prenatal human development, activated astrocytes guide endothelial cells into place where they can proliferate and form blood vessels. And later in life, activated astrocytes can also act as a template for endothelial cells to form blood vessels during angiogenesis.

Friedlander and his team found that they were able to target the activated astrocytes with the stem cell in vivo. They then tested these stem cells in a mouse model system of ocular disease. In normal mice, retinal blood vesssels form during the first three weeks after birth. In the disease model, the deeper retinal vessels completely degenerate by one month after birth.

In the ocular disease models, the stem cells differentiated into endothelial cells and proliferated, forming new blood vessels. This actually rescued and stabilized the retinal vessels when they would otherwise be degenerated.

They also found that they could shut down the angiogenesis by first transfecting the stem cells with a powerful inhibitor of angiogenesis--a fragment of the human protein tryptophanyl-tRNA synthetase (T2-TrpRS), which was discovered by TSRI Professor Paul Schimmel, Ph.D., and Friedlander and described in an article by the two investigators last year.

These transfected stem cells were also guided by the retinal astrocytes to the vasculature in the back of the eye where they expressed the T2-TrpRS protein and prevented the development of new retinal blood vessels without affecting already established blood vessels.

The research article "Bone marrow-derived stem cells target retinal astrocytes and can promote or inhibit retinal angiogenesis" is authored by Atushi Otani, Karen Kinder, Karla L. Ewalt, Francella J. Otero, Paul Schimmel, and Martin Friedlander and appears in the September, 2002 issue of Nature Medicine, appearing online as part of the advance online publication section of the journal’s web site on July 29, 2002. See http://www.nature.com/nm/.


The research was primarily funded by the National Eye Institute with additional support from The National Cancer Institute, The Skaggs Institute for Chemical Biology, The Robert Mealey Program for the Study of Macular Degenerations, Merck KgaA, and the National Foundation for Cancer Research.


Robin B. Clark | EurekAlert!
Further information:
http://www.scripps.edu/

More articles from Life Sciences:

nachricht Molecular Force Sensors
20.09.2017 | Max-Planck-Institut für Biochemie

nachricht Foster tadpoles trigger parental instinct in poison frogs
20.09.2017 | Veterinärmedizinische Universität Wien

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

Im Focus: Fast, convenient & standardized: New lab innovation for automated tissue engineering & drug

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems Holding GmbH about commercial use of a multi-well tissue plate for automated and reliable tissue engineering & drug testing.

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems...

Im Focus: Silencing bacteria

HZI researchers pave the way for new agents that render hospital pathogens mute

Pathogenic bacteria are becoming resistant to common antibiotics to an ever increasing degree. One of the most difficult germs is Pseudomonas aeruginosa, a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Molecular Force Sensors

20.09.2017 | Life Sciences

Producing electricity during flight

20.09.2017 | Power and Electrical Engineering

Tiny lasers from a gallery of whispers

20.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>