Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Bare metal stents deliver gene therapy to heart vessels with less inflammation in animal studies

20.12.2005


Improved materials may allow stents, tiny metal scaffolds inserted into blood vessels, to better deliver beneficial genes to patients with heart disease, by reducing the risk of inflammation that often negates initial benefits. The new technique, using a compound that binds in an extremely thin layer to bare metal surfaces, may have potential uses in other areas of medicine that make use of metallic implants.



Cardiologists frequently treat heart disease patients now by using stents to expand partially blocked blood vessels and improve blood flow. However, new obstructions may gradually form within the stents themselves and dangerously narrow the passageway. A newer generation of stents releases drugs to counteract this renarrowing process, called restenosis, but the polymer coatings that initially hold the drugs to the stents may stimulate inflammation. The inflammation in turn leads to restenosis.

Researchers at The Children’s Hospital of Philadelphia have developed a novel technique to attach therapeutic genes to a stent’s bare metal surface. This technique allows the genes to help heal the surrounding blood vessels, while avoiding the inflammation caused by polymer coatings.


The research team reported their proof-of-principle study, using cell culture and animal models, in the early edition of the Proceedings of the National Academy of Sciences, published online this week.

"This is the first study to demonstrate successful delivery of a gene vector from a bare metal surface," said senior author Robert J. Levy, M.D., the William J. Rashkind Chair of Pediatric Cardiology at The Children’s Hospital of Philadelphia. A gene vector is a biological substance, in this case an adenovirus, capable of delivering a therapeutic gene to target cells.

Dr. Levy’s team created a unique water-soluble compound, polyallylamine biphosphonate, that binds to the stent’s metal alloy surface in a layer with the thickness of only a single molecule. The biphosphonate holds and gradually releases adenovirus particles of the type used to deliver therapeutic genes.

In cell cultures, the adenovirus successfully delivered genes from alloy samples to animal arterial smooth muscle cells. In a second experiment using rodents, the researchers detected gene expression with significantly lower restenosis in the carotid arteries of animals with the experimental stents, compared to control animals with conventional, polymer-coated stents.

The researchers used a therapeutic gene that encodes for a protein, inducible nitric oxide synthase (iNOS), in the carotid artery studies, because of iNOS’s ability to control cell damage in blood vessels. "However, in further studies, one might use a combination of therapeutic genes or different gene vectors, for even better results," said Dr. Levy.

Metallic implants are already widely used in medicine. Some examples are artificial joints and orthopedic pins and rods, pacemaker electrodes, and titanium tooth implants. "The results of our study may have broader implications for other diseases in which implantable medical devices may be used to deliver gene therapy," said Dr. Levy.

Dr. Levy’s co-authors included Ilia Fishbein, M.D., Ivan S. Alferiev, M.D., Origene Nyanguile, Richard Gaster, and Howard Felderman, of the Children’s Hospital Division of Cardiology. Co-authors from the University of Pennsylvania were John M. Vohs and Gordon S. Wong, of the Department of Chemical and Biomolecular Engineering; Hoon Choi and I-Wei Chen, of the Department of Material Science and Engineering; and Robert L. Wilensky, of the Cardiovascular Division of the Hospital of the University of Pennsylvania.

John Ascenzi | EurekAlert!
Further information:
http://www.chop.edu

More articles from Studies and Analyses:

nachricht Smart Data Transformation – Surfing the Big Wave
02.12.2016 | Fraunhofer-Institut für Angewandte Informationstechnik FIT

nachricht Climate change could outpace EPA Lake Champlain protections
18.11.2016 | University of Vermont

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

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

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Scientists track chemical and structural evolution of catalytic nanoparticles in 3-D

08.12.2016 | Materials Sciences

Decoding cement's shape promises greener concrete

08.12.2016 | Materials Sciences

Will Earth still exist 5 billion years from now?

08.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>