A major breakthrough in stroke

Research on strokes is progressing thanks to researchers at the Blood and Brain Institute, BB@C Caen Normandie, led by Denis Vivien , professor at Caen Normandy University Hospital.
A major breakthrough recently published in the prestigious scientific journal Nature Communication .

A complex challenge to invent a contrast product

“ We have developed a new contrast product which can reveal the presence of microthrombi in magnetic resonance imaging ” explains Dr Thomas Bonnard, INSERM at the Blood and Brain Institute ( PhIND laboratory, INSERM U-1237 ).

Thrombi are clots that obstruct blood vessels , block blood flow to the brain and cause a stroke .

When a patient suffering from a stroke is brought to the hospital by the emergency services, doctors will seek to image their brain as quickly as possible with a CT scan or magnetic resonance imaging ( MRI ). With current technologies, it is possible to observe the vessels of the brain and thus understand where the blockage is located, which is already extremely useful in choosing the best intervention to carry out. We can also discern the larger thrombi responsible for these blockages. But in a certain number of cases, there are small fragments of thrombi scattered in the patient's brain called microthrombi which are impossible to observe, even with the latest CRI .

This is where the contrast product invented by Dr Charlène Jacqmarcq and Dr Thomas Bonnard . They developed magnetic microparticles intended to be injected into the bloodstream and capable of attaching to microthrombi. The magnetic properties of the microparticles confer a signal in MRI and thus enable their diagnosis. With this new contrast product called PHySIOMIC, we can see microthrombi on MRI .

The challenge was complex and the synthesis of this contrast product required several years of development and advanced expertise in chemistry and materials engineering. It notably includes an innovative organic material which uses dopamine as a raw material. Dopamine is a neurotransmitter that influences our brain. Here, this same molecule is used in a test tube to make a material called polydopamine. A material which is in the form of black jelly, completely biodegradable and which has unique properties in terms of interaction with metals. The research work of Dr. Charlène Jacqmarcq and Dr. Thomas Bonnard established that this polydopamine had a specific affinity for microthrombi. To synthesize their PHySIOMIC contrast product, they assembled this polydopamine with magnetic materials that present a signal in MRI .

Funding and partnerships

All of the work published here was covered by public funding administered by the National Research Agency (ANR), including PHySIOMIC young researcher funding.

Dr Maxime Gauberti from Caen Normandy University Hospital, author of the work, designed certain radiology experiments as part of his CCA- INSERM -Bettencourt year. A contract is also entered into with CSL-Behring, Australia's largest pharmaceutical company.

“Today, the follow-up to this project is pending as long as the patent is not filed,” explains Dr. Bonnard, who has returned from a one-year placement as part of a collaboration with an Australian laboratory. .