Ultra-small Super Paramagnetic Iron Oxide predicts higher disease activity in clinically isolated syndrome

Adil Maarouf (1, 2) , Jean Ferré (3, 4) , W Zaaraoui (1) , Arnaud Le Troter (1) , Elise Bannier (5, 4) , Isabelle Berry (6, 7) , Maxime Guye (8) , Laurent Pierot (9) , Christian Barillot (10, 4, 11) , Jean Pelletier (12) , Ayman Tourbah (9) , Gilles Edan (4, 13) , Bertrand Audoin (12) , Jean-Philippe Ranjeva (1)

1 CRMBM - Centre de résonance magnétique biologique et médicale
2 Hôpital Maison Blanche
3 Service de radiologie et imagerie médicale [Rennes] = Radiology [Rennes]
4 VisAGeS - Vision, Action et Gestion d'informations en Santé
5 Centre Hospitalier Universitaire de Rennes [CHU Rennes] = Rennes University Hospital [Ponchaillou]
6 ToNIC - Toulouse NeuroImaging Center
7 Service de Médecine Nucléaire - Pierre-Paul Riquet [CHU Toulouse]
8 CEMEREM - Centre d'Exploration Métabolique par Résonance Magnétique [Hôpital de la Timone - APHM]
9 URCA - Université de Reims Champagne-Ardenne
10 IRISA - Institut de Recherche en Informatique et Systèmes Aléatoires
11 VisAGeS - Vision, Action et Gestion d'informations en Santé
12 TIMONE - Hôpital de la Timone [CHU - APHM]
13 Service de Neurologie [Rennes] = Neurology [Rennes]

Background: Macrophages are important components of inflammatory processes in multiple sclerosis, closely linked to axonal loss, and can now be observed in-vivo using Ultra-Small super-Paramagnetic Iron Oxide (USPIO). We aimed to determine the prevalence of macrophage infiltration and to assess the predictive value on disease activity and tissue injury after one year in clinical isolated syndrome patients. Methods: Thirty-five patients were imaged using conventional-MRI, magnetization transfer ratio (MTR) to assess tissue destructuration, gadolinium (Gd) to probe blood brain barrier integrity, and USPIO to study macrophage infiltration. Results: At baseline, patients showed 17 USPIO-positive lesions reflecting infiltration of macrophages present from the onset. This infiltration was associated with higher local tissue destructuration as emphasized by lower MTR values of USPIO-positive/Gdpositive lesions compared to USPIO-negative/Gd-positive and to non-enhanced lesions, at baseline and Month-12, and no difference between USPIO-negative/Gd-positive and non-enhanced lesions. While at baseline T2-lesion load of patients with USPIOenhancement compared to patients with Gd-enhancement was not different, it was higher at Month-12. T1-lesion load was also higher at Month-12 in patients with USPIO-enhancement. Conclusion: Infiltration of activated macrophages evidenced by USPIO enhancement, is present at the onset of MS and is associated with higher local and global progression of tissue destructuration.

Mots clés: Multiple sclerosis; USPIO; macrophage; clinically isolated syndrome; MRI

Domaines: Neurosciences [q-bio.NC]

Adil Maarouf, Jean Ferré, W Zaaraoui, Arnaud Le Troter, Elise Bannier, et al.. Ultra-small Super Paramagnetic Iron Oxide predicts higher disease activity in clinically isolated syndrome. 2017. ⟨hal-01576913⟩