The white matter of the MS brain shows abnormalities even before inflammation

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system. In early, as well as advanced progressive MS, lesions arise along with substantial inflammatory activity. Lesions are the inflammatory sites where the myelin is broken down and taken up by microglial cells (our brain’s immune cells). But do we see something in the tissue even before these inflammation spots appear?

To answer this question, Aletta van den Bosch of the research team of Inge Huitinga (NIN) and Wiebke Moebius (MPI) looked into human post-mortem brains of MS patients and controls that have been donated to the Dutch Brain Bank. Their focus was particularly on the so-called ‘normal-appearing white matter’. As the name suggests, these are areas where lesions have not formed yet, and so still appear normal. How is it possible that people with MS develop lesions here later and people without MS do not?