A new Mayo Clinic study has found that the type of tissue damage changes throughout the course of multiple sclerosis (MS). In early relapsing disease stages, the plaques, or areas where the nervous system is inflamed or demyelinated, are predominantly active with distinct heterogeneous patterns of myelin damage. Later in the chronic progressive phase of the disease, smoldering and inactive plaques predominate, and are characterized by a uniform pattern of tissue damage.
This work provides important information at the microscopic level regarding the dynamic changes occurring in MS white matter plaques over the course of the disease which can help inform subsequent studies that characterize the disease based on advanced imaging techniques or clinical outcomes. A better understanding of the pathology of MS may eventually lead to new therapeutic targets.
“We have pretty good therapies to treat and reduce the frequency of relapses in MS, but as the disease progresses and the relapses become less frequent, we need to better understand the biologic basis for that progression,” says Claudia Lucchinetti, M.D., a Mayo Clinic neurologist and author of this study. “This study showed us that smoldering MS plaques are more commonly found during progressive disease phases. These plaques, unlike active MS plaques, show a limited degree of ongoing demyelination that occurs at the expanding plaque border of an established MS lesion, and are characterized by a uniform pattern of myelin damage. By studying these plaques and attempting to understand the key mechanisms involved in their formation, we can begin thinking of alternative therapies that might better target the processes that contribute to disease progression.”
Read the full news release here.
The study was presented at the American Academy of Neurology Annual Meeting in Toronto on April 14.
Below is a link to an edited video of Dr. Lucchinetti.