Aquaporin-4 (AQP4) antigenic epitopes presented on Major Histocompatibility Complex (MHC) to T-cell receptors (TCR) (AQP4-MHC-TCR)

Aquaporin-4 (AQP4) is the primary water channel protein in the central nervous system, localized predominantly on astrocyte foot processes (UniProt P55087). In Neuromyelitis Optica Spectrum Disorder (NMOSD), AQP4 is the target of an autoimmune response where its antigenic epitopes are processed and presented on Major Histocompatibility Complex (MHC) molecules, specifically HLA-DRB1*03:01, to T-cell receptors (TCRs) (Varrin-Doyer et al., 2012). This interaction is essential for the activation of AQP4-specific CD4+ T-cells, which drive the inflammatory process and support B-cell production of pathogenic AQP4-IgG antibodies (Nelson et al., 2017). While current therapies focus on B-cell depletion or complement inhibition, the AQP4-MHC-TCR complex represents a novel target for antigen-specific immunotherapies aimed at restoring immune tolerance (Zekeridou & Lennon, 2015). By selectively targeting these epitopes, researchers hope to prevent the astrocytic damage and subsequent demyelination characteristic of NMOSD without the risks associated with systemic immunosuppression. Experimental approaches include the use of tolerogenic dendritic cells or peptide-based vaccines to modulate the T-cell response. This precision medicine strategy aims to address the underlying cause of the disease rather than just managing symptoms or broad inflammation.

Other names

AQP4-specific T-cell epitopesAquaporin-4 peptide-MHC complexAQP4-TCR interactionNeuromyelitis optica autoantigenic peptides

Induction of antigen-specific immune tolerance or selective blockade of the T-cell receptor's recognition of AQP4 peptides presented on MHC class II molecules.