Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Non-invasive imaging technique detects plaques beginning to form in vessels

20.11.2002


A new imaging method successfully identifies miniscule, young blood vessels that form during the development of plaques, according to a study in rabbits led by Washington University School of Medicine in St. Louis. These plaques are akin to atherosclerosis in humans, the primary cause of heart attack and stroke.



"We’ve developed a way to take non-invasive images of very early plaques, before they’re detectable by any other means," says Samuel A. Wickline, M.D., professor of medicine and biomedical engineering and one of the study’s senior authors. "This same technology, we think, will allow us to detect very early cancers and other inflammatory events as well."

Patrick M. Winter, Ph.D., research instructor of medicine and first author of the study, presented the team’s results Nov. 19 during the Russell Ross Memorial Lecture and New Frontiers in Atherosclerosis at the American Heart Association’s Scientific Sessions 2002 in Chicago. Gregory M. Lanza, M.D., Ph.D., assistant professor of medicine and biomedical engineering, is co-senior author.


Wickline also presented an overview of molecular imaging and nanotechnology at the Molecular Basis for Cardiac Imaging session.

Atherosclerosis – the progressive hardening of arteries – results from the accumulation of plaques in key blood vessels. In order for plaques to form, a crowd of smaller vessels, called capillaries, must develop around the diseased site.

In this study, the team used a relatively new imaging method – developed primarily at Washington University – to label growing capillaries, thereby identifying locations where plaques are about to form. They loaded an extremely small particle roughly 200 nanometers long, called a nanoparticle, with about 80,000 atoms of gadolinium, which shows up as a bright spot on a magnetic resonance image (MRI). Other carriers for gadolinium hold only a few such atoms at a time, and therefore result in less bright images.

In order to ensure that gadolinium highlighted only new capillaries, the team also packed the nanoparticle with molecules that specifically detect a protein called avb3, which is abundant in rapidly growing capillaries. In so doing, the nanoparticles mainly latched onto cells that contain avb3.

"You can load these nanoparticles with whatever you want, like a Mr. Potato Head," Wickline explains. "The targeting agent allows us to select where the particle goes, and then we can either add an imaging agent, like gadolinium, or a drug, like plaque stabilizing medications or anticancer agents."

The team injected nanoparticles loaded with avb3 detectors and gadolinium into 13 rabbits. Four of the rabbits had been fed normal diets and nine had been fed high-cholesterol diets for about 80 days. They then took MRI scans of the abdominal aorta – the largest artery in the body – for two hours after injection. The cholesterol-fed rabbits injected with targeted nanoparticles had gadolinium signals in the abdominal aorta more than twice as bright as the other rabbits.

Post-mortem examination confirmed that the cholesterol-fed animals were in fact developing dangerous capillaries around the aorta, in contrast to the control diet rabbits.

"These preliminary results suggest that we can manipulate nanoparticles to image plaques as they are just beginning to form," says Wickline. "Previous research of ours also suggests that this technique can distinguish between patients with stable plaques from those whose plaques are about to rupture and thereby cause a heart attack or stroke."

Because tumors also require new populations of capillaries, the team believes this technique will enable them to detect very early cancers at the beginning stages of tumor development.


The technology used in this study has been licensed to KEREOS Inc., which is devoted to molecular imaging and targeted therapeutics. Gregory M. Lanza, M.D., Ph.D., and Samuel A. Wickline, M.D., are co-founders of KEREOS and both are board members and equity holders.

Winter PM, Caruthers SD, Schmeider A, Harris TD, Chinen L, Williams T, Watkins MP, Allen JS, Wickline SA, Lanza GM. Molecular imaging of angiogenesis in atherosclerotic rabbits by MRI at 1.5T with avb3 targeted nanoparticles, American Heart Association, Nov. 19, 2002.

Wickline SA, Lanza GM. Nanotechnology for molecular imaging and targeted therapeutics. American Heart Association, Nov. 17, 2002.

Funding from the National Heart, Lung and Blood Institute, the National Cancer Institute and Philips Medical Systems supported this research. Bristol-Myers Squibb Medical Imaging provided materials for the study.

The full-time and volunteer faculty of Washington University School of Medicine are the physicians and surgeons of Barnes-Jewish and St. Louis Children’s hospitals. The School of Medicine is one of the leading medical research, teaching and patient-care institutions in the nation. Through its affiliations with Barnes-Jewish and St. Louis Children’s hospitals, the School of Medicine is linked to BJC HealthCare.

Gila Z. Reckess | EurekAlert!
Further information:
http://medinfo.wustl.edu/

More articles from Health and Medicine:

nachricht Finnish research group discovers a new immune system regulator
23.02.2018 | University of Turku

nachricht Minimising risks of transplants
22.02.2018 | Friedrich-Alexander-Universität Erlangen-Nürnberg

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: Attoseconds break into atomic interior

A newly developed laser technology has enabled physicists in the Laboratory for Attosecond Physics (jointly run by LMU Munich and the Max Planck Institute of Quantum Optics) to generate attosecond bursts of high-energy photons of unprecedented intensity. This has made it possible to observe the interaction of multiple photons in a single such pulse with electrons in the inner orbital shell of an atom.

In order to observe the ultrafast electron motion in the inner shells of atoms with short light pulses, the pulses must not only be ultrashort, but very...

Im Focus: Good vibrations feel the force

A group of researchers led by Andrea Cavalleri at the Max Planck Institute for Structure and Dynamics of Matter (MPSD) in Hamburg has demonstrated a new method enabling precise measurements of the interatomic forces that hold crystalline solids together. The paper Probing the Interatomic Potential of Solids by Strong-Field Nonlinear Phononics, published online in Nature, explains how a terahertz-frequency laser pulse can drive very large deformations of the crystal.

By measuring the highly unusual atomic trajectories under extreme electromagnetic transients, the MPSD group could reconstruct how rigid the atomic bonds are...

Im Focus: Developing reliable quantum computers

International research team makes important step on the path to solving certification problems

Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...

Im Focus: In best circles: First integrated circuit from self-assembled polymer

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...

Im Focus: Demonstration of a single molecule piezoelectric effect

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...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Basque researchers turn light upside down

23.02.2018 | Physics and Astronomy

Finnish research group discovers a new immune system regulator

23.02.2018 | Health and Medicine

Attoseconds break into atomic interior

23.02.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>