Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Pitt develops biodegradable artery graft to enhance bypass surgeries

25.06.2012
Pitt's cell-free, biodegradable artery graft results in a regenerated artery in 90 days, leaving behind no trace of synthetic graft materials in the body

With the University of Pittsburgh's development of a cell-free, biodegradable artery graft comes a potentially transformative change in coronary artery bypass surgeries: Within 90 days after surgery, the patient will have a regenerated artery with no trace of synthetic graft materials left in the body.

Research published online June 24 in Nature Medicine highlights work led by principal investigator Yadong Wang, a professor in Pitt's Swanson School of Engineering and School of Medicine's Department of Surgery, who designed grafts that fully harness the body's regenerative capacity. This new approach is a philosophical shift from the predominant cell-centered approaches in tissue engineering of blood vessels.

"The host site, the artery in this case, is an excellent source of cells and provides a very efficient growth environment," said Wang. "This is what inspired us to skip the cell culture altogether and create these cell-free synthetic grafts."

Wang and fellow researchers, Wei Wu, a former Pitt postdoctoral associate (now a postdoctoral associate at Yale University), and Robert Allen, a PhD student in bioengineering, designed the graft with three properties in mind. First, they chose a graft material—an elastic polymer called PGS—that is resorbed quickly by the body. Then, they examined graft porosity and selected parameters that allow immediate cell infiltration. Wang's team borrowed a procedure developed by another team of Pitt researchers—David Vorp, professor of bioengineering and surgery, and William R. Wagner, interim director of the University's McGowan Institute for Regenerative Medicine and a Pitt professor of surgery, bioengineering, and chemical engineering—wrapping the vascular graft with a fibrous sheath to trap the cells. Finally, Wang and his fellow researchers wanted a coating for the grafts that would reduces blood clotting and bind many growth factors, so they used heparin, a molecule that does just that.

"The results were porous grafts that are suturable," said Wang. "And the rapid remodeling of the grafts led to strong and compliant new arteries. The extent of the changes in the grafts that occurred in just 90 days was remarkable."

Wang and his colleagues made grafts as small as 1 mm in diameter and monitored the graft's transformation in vivo for three months. Because the graft was highly porous, cells were easily able to penetrate the graft wall, and mononuclear cells occupied many of the pores within three days. Within 14 days, smooth muscle cells—an important blood vessel builder—appeared. At 28 days, cells were distributed more evenly throughout the graft. At 90 days, most inflammatory cells were gone, which correlated with the disappearance of the graft materials. The artery was regenerated in situ and pulsed in sync with the host. Furthermore, the composition and properties of the new arteries are nearly the same as native arteries.

"This report is the first that shows a nearly complete transformation of a synthetic plastic tube to a new host artery with excellent integration within three months," said Wang. "Most likely, the amount of time it takes to regenerate an artery can be further shortened as we refine the system."

Current approaches toward tissue-engineered arteries require a long production cycle because of the required cell culture steps. The newly developed graft is made in a few days, stores in a dry pouch at ambient temperature, and is readily available off the shelf. The ease of use and storage are similar to the conventional Dacron® grafts.

The project was funded by the National Heart, Lung, and Blood Institute, part of the National Institutes of Health.

B. Rose Huber | EurekAlert!
Further information:
http://www.pitt.edu

More articles from Health and Medicine:

nachricht New discoveries predict ability to forecast dementia from single molecule
12.12.2018 | UT Southwestern Medical Center

nachricht Pain: Perception and motor impulses arise in the brain independently of one another
12.12.2018 | Technische Universität München

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: Lethal combination: Drug cocktail turns off the juice to cancer cells

A widely used diabetes medication combined with an antihypertensive drug specifically inhibits tumor growth – this was discovered by researchers from the University of Basel’s Biozentrum two years ago. In a follow-up study, recently published in “Cell Reports”, the scientists report that this drug cocktail induces cancer cell death by switching off their energy supply.

The widely used anti-diabetes drug metformin not only reduces blood sugar but also has an anti-cancer effect. However, the metformin dose commonly used in the...

Im Focus: New Foldable Drone Flies through Narrow Holes in Rescue Missions

A research team from the University of Zurich has developed a new drone that can retract its propeller arms in flight and make itself small to fit through narrow gaps and holes. This is particularly useful when searching for victims of natural disasters.

Inspecting a damaged building after an earthquake or during a fire is exactly the kind of job that human rescuers would like drones to do for them. A flying...

Im Focus: Topological material switched off and on for the first time

Key advance for future topological transistors

Over the last decade, there has been much excitement about the discovery, recognised by the Nobel Prize in Physics only two years ago, that there are two types...

Im Focus: Researchers develop method to transfer entire 2D circuits to any smooth surface

What if a sensor sensing a thing could be part of the thing itself? Rice University engineers believe they have a two-dimensional solution to do just that.

Rice engineers led by materials scientists Pulickel Ajayan and Jun Lou have developed a method to make atom-flat sensors that seamlessly integrate with devices...

Im Focus: Three components on one chip

Scientists at the University of Stuttgart and the Karlsruhe Institute of Technology (KIT) succeed in important further development on the way to quantum Computers.

Quantum computers one day should be able to solve certain computing problems much faster than a classical computer. One of the most promising approaches is...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

ICTM Conference 2019: Digitization emerges as an engineering trend for turbomachinery construction

12.12.2018 | Event News

New Plastics Economy Investor Forum - Meeting Point for Innovations

10.12.2018 | Event News

EGU 2019 meeting: Media registration now open

06.12.2018 | Event News

 
Latest News

New discoveries predict ability to forecast dementia from single molecule

12.12.2018 | Health and Medicine

CCNY-Yale researchers make shape shifting cell breakthrough

12.12.2018 | Physics and Astronomy

Pain: Perception and motor impulses arise in the brain independently of one another

12.12.2018 | Health and Medicine

VideoLinks
Science & Research
Overview of more VideoLinks >>>