Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Pitt develops biodegradable artery graft to enhance bypass surgeries

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:

More articles from Health and Medicine:

nachricht Advanced analysis of brain structure shape may track progression to Alzheimer's disease
26.10.2016 | Massachusetts General Hospital

nachricht Indian roadside refuse fires produce toxic rainbow
26.10.2016 | Duke University

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: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

All Focus news of the innovation-report >>>



Event News

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

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

How nanoscience will improve our health and lives in the coming years

27.10.2016 | Materials Sciences

OU-led team discovers rare, newborn tri-star system using ALMA

27.10.2016 | Physics and Astronomy

'Neighbor maps' reveal the genome's 3-D shape

27.10.2016 | Life Sciences

More VideoLinks >>>