Formation and immunomodulatory function of meningeal B cell aggregates in progressive CNS autoimmunity

Mitsdoerffer, Meike; Di Liberto, Giovanni; Doetsch, Sarah; Sie, Christopher; Wagner, Ingrid; Pfaller, Monika; Kreutzfeldt, Mario; Fraessle, Simon; Aly, Lilian; Knier, Benjamin; Busch, Dirk H.; Merkler, Doron und Korn, Thomas (2021): Formation and immunomodulatory function of meningeal B cell aggregates in progressive CNS autoimmunity. In: Brain, Bd. 144: S. 1697-1710

Abstract

Meningeal B lymphocyte aggregates have been described in autopsy material of patients with chronic multiple sclerosis. The presence of meningeal B cell aggregates has been correlated with worse disease. However, the functional role of these meningeal B cell aggregates is not understood. Here, we use a mouse model of multiple sclerosis, the spontaneous opticospinal encephalomyelitis model, which is built on the double transgenic expression of myelin oligodendrocyte glycoprotein-specific T-cell and B-cell receptors, to show that the formation of meningeal B cell aggregates is dependent on the expression of alpha 4 integrins by antigen-specific T cells. T cell-conditional genetic ablation of alpha 4 integrins in opticospinal encephalomyelitis mice impaired the formation of meningeal B cell aggregates, and surprisingly, led to a higher disease incidence as compared to opticospinal encephalomyelitis mice with alpha 4 integrin-sufficient T cells. B cell-conditional ablation of alpha 4 integrins in opticospinal encephalomyelitis mice resulted in the entire abrogation of the formation of meningeal B cell aggregates, and opticospinal encephalomyelitis mice with alpha 4 integrin-deficient B cells suffered from a higher disease burden than regular opticospinal encephalomyelitis mice. While anti-CD20 antibody-mediated systemic depletion of B cells in opticospinal encephalomyelitis mice after onset of disease failed to efficiently decrease meningeal B cell aggregates without significantly modulating disease progression, treatment with anti-CD19 chimeric antigen receptor-T cells eliminated meningeal B cell aggregates and exacerbated clinical disease in opticospinal encephalomyelitis mice. Since about 20% of B cells in organized meningeal B cell aggregates produced either IL-10 or IL-35, we propose that meningeal B cell aggregates might also have an immunoregulatory function as to the immunopathology in adjacent spinal cord white matter. The immunoregulatory function of meningeal B cell aggregates needs to be considered when designing highly efficient therapies directed against meningeal B cell aggregates for clinical application in multiple sclerosis.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Medizin > Munich Cluster for Systems Neurology (SyNergy)
• Themengebiete: 600 Technik, Medizin, angewandte Wissenschaften > 610 Medizin und Gesundheit
• Sprache: Englisch
• DFG: Gefördert durch die Deutsche Forschungsgemeinschaft (DFG) - 390857198