As inflammatory processes take part in the pathogenesis of MS, we questioned whether an important inflammatory mediator, IL-1β and, its functional counteracting partner, IL-1ra are present in affected WM and GM regions in the CNS during cr-EAE in DA rats, an experimental animal model, mimicking some pathological aspects of relapsing-remitting MS. Here, IL1B is linked to relapsing-remitting multiple sclerosis.