PET detects neuroinflammation in multiple sclerosis

June 12, 2016

San Diego, Calif. - The triggers of autoimmune inflammation in multiple sclerosis (MS) have eluded scientists for many years, but molecular imaging is bringing researchers closer to identifying them, while providing a means of evaluating next-generation therapies for MS, say researchers introducing a study at the 2016 Annual Meeting of the Society of Nuclear Medicine and Molecular Imaging (SNMMI).

More than 2.3 million people are affected by MS worldwide, according to estimates from the National Multiple Sclerosis Society. MS is marked by inflammation and the systematic destruction of neuronal fibers, specifically myelin, in the nervous system. Myelin is the fatty layer that both protects the fibers and increases the speed of signaling along the axon of nerve cells. Similar inflammatory processes are typical in the pathology of other neurodegenerative diseases such as Parkinson's and Alzheimer's, gastrointestinal diseases like Crohn's and ulcerative colitis, and the vascular inflammation that leads to atherosclerosis.

"Inflammation is the body's physiological defense to harmful stimuli and it plays a critical role in the immune response to injury and infection," said senior investigator, Zhude Tu, PhD, professor of PET radiochemistry at Washington University School of Medicine in St. Louis, Mo. "However, despite the benefits of acute inflammation in promoting healing, these same processes are associated with numerous pathological conditions when chronic inflammation is left unchecked."

This study furthers a growing body of research pointing to a process called sphingolipid signaling as a primary mechanism in inflammatory disease processes. The FDA approval in 2010 of fingolimod for relapsing MS further supports the hypotheses that the sphingosine-1-phosphate receptor 1 (S1P1) is an ideal biomarker for imaging and new therapies. Fingolimod works by turning down the autoimmune response via immune cell S1P1.

First author of the study Adam J. Rosenberg, PhD, and his colleagues produced a library of S1P1-targeted small molecules and radiolabeled them with fluorine-18. These radiotracers bind directly to S1P1 receptors and can be imaged with preclinical positron emission tomography (PET), through noninvasive methodology to investigate the physiological functions of S1P1 receptors in animal models as a precursor for human studies. In this case, researchers imaged S1P1 in rodent models of inflammatory disease and healthy controls. They found that the PET imaging agents not only were able to detect an increase in S1P1 expression in animals with an inflammatory response when compared to healthy controls, but that the compounds also crossed the blood brain barrier in healthy animals, a significant limiting factor in the development of central nervous system drugs.

"These compounds represent promising PET tracers for imaging MS and other inflammatory diseases by quantitative assessment of S1P1 expression in the body," said Tu.
-end-
Scientific Paper 1: "Development and in vivo evaluation of three F-18 labeled S1P1 ligands as PET tracers for MS," A. J. Rosenberg, H. Liu, X. Yue, H. Jin, Z. Tu, Washington University School of Medicine, St. Louis, Mo., SNMMI's 63rd Annual Meeting, June 11-15, 2016, San Diego, Calif.

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 17,000 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.

Society of Nuclear Medicine

Related Multiple Sclerosis Articles from Brightsurf:

New therapy improves treatment for multiple sclerosis
A new therapy that binds a cytokine to a blood protein shows potential in treating multiple sclerosis, and may even prevent it.

'Reelin' in a new treatment for multiple sclerosis
In an animal model of multiple sclerosis (MS), decreasing the amount of a protein made in the liver significantly protected against development of the disease's characteristic symptoms and promoted recovery in symptomatic animals, UTSW scientists report.

Not all multiple sclerosis-like diseases are alike
Scientists say some myelin-damaging disorders have a distinctive pathology that groups them into a unique disease entity.

New therapeutic options for multiple sclerosis in sight
Strategies for treating multiple sclerosis have so far focused primarily on T and B cells.

Diet has an impact on the multiple sclerosis disease course
The short-chain fatty acid propionic acid influences the intestine-mediated immune regulation in people with multiple sclerosis (MS).

The gut may be involved in the development of multiple sclerosis
It is incompletely understood which factors in patients with multiple sclerosis act as a trigger for the immune system to attack the brain and spinal cord.

Slowing the progression of multiple sclerosis
Over 77,000 Canadians are living with multiple sclerosis, a disease whose causes still remain unknown.

7T MRI offers new insights into multiple sclerosis
Investigators from Brigham and Women's Hospital have completed a new study using 7 Tesla (7T) MRI -- a far more powerful imaging technology -- to further examine LME in MS patients

How to improve multiple sclerosis therapy
Medications currently used to treat multiple sclerosis (MS) can merely reduce relapses during the initial relapsing-remitting phase.

Vaccinations not a risk factor for multiple sclerosis
Data from over 12,000 multiple sclerosis (MS) patients formed the basis of a study by the Technical University of Munich (TUM) which investigated the population's vaccination behavior in relation to MS.

Read More: Multiple Sclerosis News and Multiple Sclerosis Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.