BBB breakdown and leakage in MS

"Leakage of molecules across the BBB tended to be greater where there were more tight junction abnormalities (makes sense), and while leakage was especially pronounced in active lesions, it was also present in inactive lesions, demonstrating that vessel damage tends to persist even in older lesions. Another interesting finding was that tight junction abnormalities were found in vessels of all types, not just the ones through which inflammatory cells would be expected to infiltrate. This indicates that the breakdown is not caused by infiltration itself but perhaps instead by a pervasive factor such as the release of inflammatory molecules.

Studies like this are important in understanding the sequence of events in MS and deciding the critical events or interactions to target with new therapies. Further study should clarify whether BBB breakdown is essential in the formation of new lesions and therefore whether new therapies to prevent leakage could slow the progression of the disease."