Neuroinflammation is often associated with blood-brain-barrier dysfunction, which contributes to neurological tissue damage. In a paper published in the renowned journal Nature Communications SFB 128 scientists from Mueenster reveal the pathophysiology of Susac syndrome (SuS), an enigmatic neuroinflammatory disease with central nervous system (CNS) endotheliopathy. By investigating immune cells from the blood, cerebrospinal fluid, and CNS of SuS patients, Dr. Catharina Gross and her team demonstrate oligoclonal expansion of terminally differentiated activated cytotoxic CD8+ T cells (CTLs). Neuropathological data derived from both SuS patients and a newly-developed transgenic mouse model recapitulating the disease indicate that CTLs adhere to CNS microvessels in distinct areas and polarize granzyme B, which most likely results in the observed endothelial cell injury and microhemorrhages. The autors show that blocking T-cell adhesion by anti-α4 integrin-intervention ameliorates the disease in the preclinical model. Similarly, disease severity decreases in four SuS patients treated with natalizumab along with other therapy. Their study identifies CD8+ T-cell-mediated endotheliopathy as a key disease mechanism in SuS and highlights therapeutic opportunities.
Adapted from: Gross CC, Meyer C, Bhatia U, Yshii L, Kleffner I, Bauer J, Tröscher AR, Schulte-Mecklenbeck A, Herich S, Schneider-Hohendorf T, Plate H, Kuhlmann T, Schwaninger M, Brück W, Pawlitzki M, Laplaud DA, Loussouarn D, Parratt J, Barnett M, Buckland ME, Hardy TA, Reddel SW, Ringelstein M, Dörr J, Wildemann B, Kraemer M, Lassmann H, Höftberger R, Beltrán E, Dornmair K, Schwab N, Klotz L, Meuth SG, Martin-Blondel G, Wiendl H, Liblau R. CD8+ T cell-mediated endotheliopathy is a targetable mechanism of neuro-inflammation in Susac syndrome. Nat Commun. 2019 Dec 18;10(1):5779.