Abstract
Neuromyelitis optica (NMO) is an autoimmune disorder of the central nervous system (CNS) mediated by antibodies to the water channel protein AQP4 expressed in astrocytes. The contribution of AQP4-specific T cells to the class switch recombination of pathogenic AQP4-specific antibodies and the inflammation of the blood-brain barrier is incompletely understood, as immunogenic naturally processed T-cell epitopes of AQP4 are unknown. By immunizing Aqp4(-/-) mice with full-length murine AQP4 protein followed by recall with overlapping peptides, we here identify AQP4(201-220) as the major immunogenic IA(b)-restricted epitope of AQP4. We show that WT mice do not harbor AQP4(201-220)-specific T-cell clones in their natural repertoire due to deletional tolerance. However, immunization with AQP4(201-220) of Rag1(-/-) mice reconstituted with the mature T-cell repertoire of Aqp4(-/-) mice elicits an encephalomyelitic syndrome. Similarly to the T-cell repertoire, the B-cell repertoire of WT mice is purged of AQP4-specific B cells, and robust serum responses to AQP4 are only mounted in Aqp4(-/-) mice. While AQP4(201-220)-specific T cells alone induce encephalomyelitis, NMO-specific lesional patterns in the CNS and the retina only occur in the additional presence of anti-AQP4 antibodies. Thus, failure of deletional T-cell and B-cell tolerance against AQP4 is a prerequisite for clinically manifest NMO.
Dokumententyp: | Zeitschriftenartikel |
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Fakultät: | Chemie und Pharmazie > Department Biochemie |
Themengebiete: | 500 Naturwissenschaften und Mathematik > 540 Chemie |
ISSN: | 0014-2980 |
Sprache: | Englisch |
Dokumenten ID: | 54144 |
Datum der Veröffentlichung auf Open Access LMU: | 14. Jun. 2018, 09:55 |
Letzte Änderungen: | 04. Nov. 2020, 13:33 |