The article presents abstracts of research papers on relapse in multiple sclerosis and its relation to the peripheral and central immune system. They include "Interaction between systemic inflammation and brain inflammation in chronic neurodegeneration," "Molecular mechanisms of T cell migration across the blood-brain barrier," "Antigen presentation during autoimmune CNS inflammation: killers, victims and the snitch who plays them both!," and "Glial cells as inducers of immune cell entry and activation in the brain."