OCLN and myeloid sarcoma: As peripheral blood leukocytes from MS patients were reported to increase ectopic expression of both CLN-5 and occludin during disease relapse, and down regulate them in remission or following anti-inflammatory therapy [95], it is tempting to speculate EVs mediate transfer of TJ proteins from endothelial cells—in particular BMEC—to leukocytes during neuroinflammation.