1. From the Partners Pediatric Multiple Sclerosis Center, Massachusetts General Hospital, Boston (T.C.); Montreal Neurological Institute, McGill University, and NeuroRx Research — both in Montreal (D.L.A.); Children’s Hospital of Philadelphia (B.B.) and the Center for Neuroinflammation and Experimental Neurotherapeutics and the Department of Neurology (A.B.-O.), Perelman School of Medicine, University of Pennsylvania — all in Philadelphia; the Department of Neuropathology (W.B.) and the Department of...