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 Novel chip-based gene expression tool analyzes RNA quickly and accurately
18.01.2018 | University of Illinois College of Engineering

nachricht Potentially life-saving health monitor technology designed by Sussex University physicists
10.01.2018 | University of Sussex

All articles from Medical Engineering >>>

The most recent press releases about innovation >>>

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

Im Focus: Scientists decipher key principle behind reaction of metalloenzymes

So-called pre-distorted states accelerate photochemical reactions too

What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...

Im Focus: The first precise measurement of a single molecule's effective charge

For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.

Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...

Im Focus: Paradigm shift in Paris: Encouraging an holistic view of laser machining

At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.

No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...

Im Focus: Room-temperature multiferroic thin films and their properties

Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.

Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...

Im Focus: A thermometer for the oceans

Measurement of noble gases in Antarctic ice cores

The oceans are the largest global heat reservoir. As a result of man-made global warming, the temperature in the global climate system increases; around 90% of...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

10th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Münster, 10-11 April 2018

08.01.2018 | Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

 
Latest News

Novel chip-based gene expression tool analyzes RNA quickly and accurately

18.01.2018 | Medical Engineering

Scientists on the road to discovering impact of urban road dust

18.01.2018 | Ecology, The Environment and Conservation

Gran Chaco: Biodiversity at High Risk

17.01.2018 | Ecology, The Environment and Conservation

VideoLinks
B2B-VideoLinks
More VideoLinks >>>