Antibodies (green) against neurofascin bind to the unmyelinated nodes of Ranvier (blue) in axons (red).
MS is triggered when T cells breach the blood–brain barrier and produce inflammatory cytokines that activate myelin-scavenging macrophages, causing damage to the myelin sheath. Myelin-specific antibodies that enter the brain in the T cells' wake enhance the destruction of the sheath and exacerbate disease. Researchers have blamed this myelin destruction for the neurological problems of patients with MS. But in some patients, damage happens not just to the myelin, but to the axons themselves. Because myelin can be replaced, axon damage is now considered to be the cause of permanent disability.
Mathey et al. now find that some MS patients have antibodies that attack the parts of axons...
