The study was published early online on August 23, 2010 in the Journal of Biomedical Materials Research and was funded by the National Institutes of Health.
"One of the biggest problems with any kind of implanted device, such as pacemaker, a chemotherapy port or the glucose sensors necessary to monitor blood sugar levels in diabetic patients, is the body's natural reaction to recognize it as foreign and form a scar around it," said Stuart Williams, PhD, scientific director of the CII and a senior investigator on the study. "Scars have very little blood flow and because this connection between the body and the device is compromised, the function of the device over time can decline, threatening health and leading to additional interventions to replace it."
The researchers sought to prevent the formation of scar tissue around an implanted device by "pre-vascularizing" the device just prior to implantation. The investigators call this a microvascular construct (MVC) consisting of tiny blood vessel fragments suspended in a collagen gel. The combination of the MVC, already rich with blood vessels, and the device appears to provide an environment that resists the formation of scar tissue once the device is implanted, Williams said.
"This study built on our earlier work that showed that this material, what we call an MVC, stimulates circulation and prevents scarring when implanted in the body, in animal models," said James Hoying, PhD, director of cardiovascular therapeutics at the CII and a senior investigator on this study. "We wanted to next see if we could maintain that circulation in order to prevent scarring over the long term and thus prolong the function of any number of implanted devices."
The researchers compared the tissue surrounding a bare expanded polytetrafluoroethylene material – implanted biomaterial many devices are made of – embedded in collagen alone to one embedded in collagen and the MVC, and found that the latter both promoted and maintained circulation in the area around the implant, Williams said. Animal models were used. Collagen is a naturally occurring protein found in the flesh and connective tissue of animals and humans. It has been found to mediate the inflammatory reaction that often occurs when an implanted device interacts with surrounding tissue.
"We found that the presence of the MVCs and collagen altered the way tissue formed around the implants, restricting the formation of scar tissue because there was so much blood vessel activity," Williams said. "The presence of the MVCs and collagen also reduced the number of white blood cells that stimulate inflammation, where the device was implanted. The vessels associated with the implant were seen to be capable of sustainable blood delivery over time."
All of these factors are important in sustaining circulation and suppressing scar formation, he said.
Williams and colleagues are now working to design an operating room-compatible device that could bring this technology to patients.
"This could have implications for patients who have any number of implantable devices, from those on dialysis to patients with devices that help failing hearts to function, to those receiving chemotherapy, catheters and multiple other indications," Williams said.
Other investigators involved in this study include Gabriel Gruionu, Alice Stone, and Mark Schwartz of the University of Arizona, Tucson.
The mission of the CII is to promote research focused on combating cardiovascular disease, taking new therapies from discovery to treatment, becoming a partner in the development, testing and commercialization of breakthrough innovations and making important and lasting contributions to the practice of cardiovascular medicine.
Lauren Williams | EurekAlert!
Rutgers-led innovation could spur faster, cheaper, nano-based manufacturing
14.02.2018 | Rutgers University
New study from the University of Halle: How climate change alters plant growth
12.01.2018 | Martin-Luther-Universität Halle-Wittenberg
For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.
In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...
Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale
Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...
For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.
But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...
Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.
The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...
Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters
Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...
15.02.2018 | Event News
13.02.2018 | Event News
12.02.2018 | Event News
20.02.2018 | Life Sciences
20.02.2018 | Medical Engineering
20.02.2018 | Physics and Astronomy