Shang, Ke

Chimeric antigen receptor (CAR) T cell immunotherapy for the treatment of neurological autoimmune diseases is promising, but CAR T cell kinetics and immune alterations after treatment are poorly understood. Here, we performed single-cell multi-omics sequencing of paired cerebrospinal fluid (CSF) and blood samples from patients with neuromyelitis optica spectrum disorder (NMOSD) treated with anti–B cell maturation antigen (BCMA) CAR T cells. Proliferating cytotoxic-like CD8 + CAR T cell clones were identified as the main effectors in autoimmunity. Anti-BCMA CAR T cells with enhanced features of chemotaxis efficiently crossed the blood-CSF barrier, eliminated plasmablasts and plasma cells in the CSF, and suppressed neuroinflammation. The CD44-expressing early memory phenotype in infusion products was potentially associated with CAR T cell persistence in autoimmunity. Moreover, CAR T cells from patients with NMOSD displayed distinctive features of suppressed cytotoxicity compared with those from hematological malignancies. Thus, we provide mechanistic insights into CAR T cell function in patients with neurological autoimmune disease.

Background and Purpose— White matter (WM) ischemic injury, a major neuropathological feature of cerebral small vessel diseases, is an important cause of vascular cognitive impairment in later life. The pathogenesis of demyelination after WM ischemic damage are often accompanied by microglial activation. Fingolimod (FTY720) was approved for the treatment of multiple sclerosis for its immunosuppression property. In this study, we evaluated the neuroprotective potential of FTY720 in a WM ischemia model. Methods— Chronic WM ischemic injury model was induced by bilateral carotid artery stenosis. Cognitive function, WM integrity, microglial activation, and potential pathway involved in microglial polarization were assessed after bilateral carotid artery stenosis. Results— Disruption of WM integrity was characterized by demyelination in the corpus callosum and disorganization of Ranvier nodes using Luxol fast blue staining, immunofluorescence staining, and electron microscopy. In addition, radial maze test demonstrated that working memory performance was decreased at 1-month post–bilateral carotid artery stenosis–induced injury. Interestingly, FTY720 could reduce cognitive decline and ameliorate the disruption of WM integrity. Mechanistically, cerebral hypoperfusion induced microglial activation, production of associated proinflammatory cytokines, and priming of microglial polarization toward the M1 phenotype, whereas FTY720 attenuated microglia-mediated neuroinflammation after WM ischemia and promoted oligodendrocytogenesis by shifting microglia toward M2 polarization. FTY720’s effect on microglial M2 polarization was largely suppressed by selective signal transducer and activator of transcription 3 (STAT3) blockade in vitro, revealing that FTY720-enabled shift of microglia from M1 to M2 polarization state was possibly mediated by STAT3 signaling. Conclusions— Our study suggested that FTY720 might be a potential therapeutic drug targeting brain inflammation by skewing microglia toward M2 polarization after chronic cerebral hypoperfusion.