EAE is induced to susceptible mice using linear
peptides of
myelin proteins of the central nervous system. Specific
peptide motifs within the
peptide-binding groove of the MHC
peptide-complex determines the affinity of the
peptide in each animal and the consequent
T-cell receptor recognition and activation of the cell. Altered
peptide ligand (APL) vaccination is a novel approach based on an effort to induce T-cell tolerance or alter
cytokine profile from pro-inflammatory to anti-inflammatory. In the present study we synthesized the MOG35-55
peptide and altered its 3-dimensional conformation to make it a cyclic one (c-MOG35-55). EAE was induced in C57BL/6 mice and pathology was studied on acute and chronic phase of the disease. Our data indicates that c-MOG35-55
peptide alone induces a mild transient acute phase without chronic axonopathy. Administration of the c-MOG35-55
peptide at a 1:1 ratio during disease induction significantly ameliorates clinical disease and underlying pathology, such as
demyelination and axonopathy in the acute and chronic phases. Binding and structural studies revealed milder interactions between the c-MOG35-55 and mouse or human MHC class II alleles (H2-IAb and HLA-DR2). Collectively, we provide data supporting for the first time the concept that the cyclic modification of an established encephalitogenic
peptide ameliorates the clinical outcomes and underlying
pathological processes of EAE. Such a cyclic modification of linear
peptides could provide a novel treatment approach for future, patient-selective, immunomodulative treatments of
multiple sclerosis.