Clinical Research Directory

20 healthy volunteers will be included for MRI normalization Volunteer eligibility criteria Inclusion criteria : * Age 18-50 years * ASA 1 classification (healthy patient) Exclusion criteria : * Lack of written consent * Neurological history likely to alter the image (epilepsy, transient ischaemic attack, meningitis, head trauma) * Vulnerable person according to article L1121-6 of the CSP * Protected adult person * No affiliation to a social security regime * Pregnancy * Contraindication for MRI and PET-MRI * patients with Pacemaker and defibrillator * MR-incompatible prosthetic heart valve * Metallic intraocular, intra cerebral or intra medullary foreign bodies * Implantable neurostimulation systems * Cochlear implants/ear implant * Metallic fragments such as bullets, shotgun pellets, and metal shrapnel * Cerebral artery aneurysm clips * Ventriculo peritoneal shunt with metallic component generating significant artefacts on the MR sequence * Catheters with metallic components (Swan-Ganz catheter) * Patient unable to remain supine and motionless during the duration of the examination 68 severe TBI patients with the following inclusion and exclusion criteria will be included" Patient Inclusion criteria * Age 18-50 years * Severe TBI defined by: * Glasgow score \<12 within the 48 first hours, * Brain traumatic lesion on CT scan, * Need for intracranial pressure monitoring * No other significant organ trauma (AIS \<2) * Unresponsive to verbal commands 5 days after sedation discontinuation, for whom, after usual clinical and paraclinical evaluation there has been no decision to interrupt active therapies within 10 days after sedation discontinuation * Written consent signed by the close relative Patient Exclusion criteria * History of disease or treatment impairing current or previous year immunity function ( hematologic disease (leukemia, myeloma), viral disease affecting immunity (like HIV), immunological treatment (corticoid, anti rejection medication, anti TNFα, chemotherapy) * History of severe neurological or psychiatric disease likely to alter neurological assessment * HTAP \> grade III OMS/WHO * Ongoing uncontrolled infection with organ failure (septic shock, ARDS) including those due to severe COVID-19 * Platelets \<100 G/L or \<100000/μL, Hb \<8 g/dL, lymphocytes count \<1.5 G/L or 1500 μL , neutrophils count \< 2.5G/L or \<2500/μL, , creatinin \> 100 μmol/L * Liver function abnormalities (bilirubin\> 2.5mg / dL or transaminases\> 5x the ULN). Patients with Gilbert's disease are eligible if liver tests are normal excluding bilirubinemia * Known HIV seropositivity * Neoplasia ongoing or treated in the 3 years before screening * Bone marrow transplant recipient * History of transfusion reaction or hypersensitivity * Pregnancy * Contraindication for MRI and PET-MRI: * Patient with Pacemaker and defibrillator * MR-incompatible prosthetic heart valve o Metallic intraocular, intra cerebral or intra medullary foreign bodies * Implantable neurostimulation systems o Cochlear implants/ ear implant * Metallic fragments such as bullets, shotgun pellets, and metal shrapnel * Cerebral artery aneurysm clips * Ventriculo peritoneal shunt with metallic component generating significant artefacts on the MR sequence * Catheters with metallic components (Swan-Ganz catheter) * Patient unable to remain supine and motionless during the duration of the examination * Participation in another interventional clinical trial of an investigational therapy within 30 days of consent * No affiliation to a social security regime * Vulnerable person according to article L1121-6 of the CSP * Protected adult person