Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Novel PET tracer identifies most bacterial infections

06.10.2017

The new imaging agent offers a non-invasive method of detecting infection and monitoring antibiotic therapy

Stanford University medical scientists have developed a novel imaging agent that could be used to identify most bacterial infections. The study is the featured basic science article in The Journal of Nuclear Medicine's October issue.


This figure shows A) bioluminescence images of CD1 mice bearing P. aeruginosa-infected wound (left panel) and control mice (right panel), and B) sagittal slices from micro PET/CT scan of the same mice 1 hour after intravenous administration of 6"-18F-fluoromaltotriose.

Courtesy of Sam Gambhir, MD, PhD, Stanford University

Bacteria are good at mutating to become resistant to antibiotics. As one way to combat the problem of antimicrobial resistance, the Centers for Disease Control and Prevention (CDC) has called for the development of novel diagnostics to detect and help manage the treatment of infectious diseases.

"We really lack tools in the clinic to be able to visualize bacterial infections," explains Sanjiv Sam Gambhir, MD, PhD, chair of the Radiology Department and director of Precision Health and Integrated Diagnostics at Stanford University in California.

"What we need is something that bacteria eat that your cells, so-called mammalian cells, do not. As it turns out, there is such an agent, and that agent is maltose, which is taken up only by bacteria because they have a transporter, called a maltodextrine transporter, on their cell wall that is able to take up maltose and small derivatives of maltose."

The traditional way of diagnosing bacterial infection involves biopsy of the infected tissue and/or blood and culture tests. Gambhir and colleagues developed a new positron emission tomography (PET) tracer, 6"-18F-fluoromaltotriose, that offers a non-invasive means of detection.

The agent is a derivative of maltose and is labeled with radioactive fluorine-18 (18F). For this study, the tracer was evaluated in several clinically relevant bacterial strains in cultures and in mouse models using a micro-PET/CT scanner. Its use to help monitor antibiotic therapies was also evaluated in rats.

The results show that 6"-18F-fluoromaltotriose was taken up in both gram-positive and gram-negative bacterial strains, and it was able to detect Pseudomonas aeruginosa in a clinically relevant mouse model of wound infection.

Gambhir points out, "This is the first time this particular maltotriose, labeled with fluorine-18, has been synthesized and used in animal models. It's able to pick up bacteria that may be present anywhere throughout your body, and it does not lead to an imaging signal from a site of infection that does not involve bacteria."

He notes that the new agent even identified an infection in the heart of an animal. "We could pick up very small bacterial foci in a heart valve. And then when those animals were treated with an antibiotic, we could see that the signal went away in the heart. So, the properties of the tracer of sensitivity, specificity, low background signal throughout the animal are now facilitating its translation into humans."

The results of this pre-clinical study demonstrate that 6"-18F-fluoromaltotriose is a promising new tracer for diagnosing most bacterial infections and has the potential to change the clinical management of patients suffering from infectious diseases of bacterial origin.

Looking ahead, Gambhir says, "The hope is that in the future when someone has a potential infection, this approach of injecting the patient with fluoromaltotriose and imaging them in a PET scanner will allow localization of the signal and, therefore, the bacteria. And then, as one treats them, one can verify that the treatment is actually working - so that if it's not working, one can quickly change to a different treatment (for example, a different antibiotic). These kinds of findings are very important for patients, because they will very likely lead to entirely new ways to manage patients with bacterial infections, no matter where those infections might be hiding in the body."

###

The authors of "Specific Imaging of Bacterial Infection using 6"-18F-Fluoromaltotriose: A Second-Generation PET Tracer Targeting the Maltodextrin Transporter in Bacteria" include Gayatri Gowrishankar, Jonathan Hardy, Mirwais Wardak, Mohammad Namavari, Robert E. Reeves, Evgenios Neofytou, Ananth Srinivasan, Joseph C. Wu, Christopher H. Contag, and Sanjiv Sam Gambhir, Stanford University School of Medicine, Stanford, California.

Please visit the SNMMI Media Center to view the PDF of the study, including images, and more information about molecular imaging and personalized medicine. To schedule an interview with the researchers, please contact Laurie Callahan at 703-652-6773 or lcallahan@snmmi.org. Current and past issues of The Journal of Nuclear Medicine can be found online at http://jnm.snmjournals.org.

About the Society of Nuclear Medicine and Molecular Imaging

The Society of Nuclear Medicine and Molecular Imaging (SNMMI) is an international scientific and medical organization dedicated to raising public awareness about nuclear medicine and molecular imaging, a vital element of today's medical practice that adds an additional dimension to diagnosis, changing the way common and devastating diseases are understood and treated and helping provide patients with the best health care possible.

SNMMI's more than 15,000 members set the standard for molecular imaging and nuclear medicine practice by creating guidelines, sharing information through journals and meetings and leading advocacy on key issues that affect molecular imaging and therapy research and practice. For more information, visit http://www.snmmi.org.

Media Contact

Laurie Callahan
lcallahan@snmmi.org

 @SNM_MI

http://www.snm.org 

Laurie Callahan | EurekAlert!

More articles from Medical Engineering:

nachricht A 15-minute scan could help diagnose brain damage in newborns
15.11.2018 | Imperial College London

nachricht NIH scientists combine technologies to view the retina in unprecedented detail
14.11.2018 | NIH/National Eye Institute

All articles from Medical Engineering >>>

The most recent press releases about innovation >>>

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

Im Focus: UNH scientists help provide first-ever views of elusive energy explosion

Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.

Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

Purdue cancer identity technology makes it easier to find a tumor's 'address'

16.11.2018 | Health and Medicine

Good preparation is half the digestion

16.11.2018 | Life Sciences

Microscope measures muscle weakness

16.11.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>