Mannosylated PLP139-151 induces peptide-specific tolerance to experimental autoimmune encephalomyelitis

SJL mice immunized with mannosylated (M-) PLP139-151 in complete adjuvant do not develop EAE and little CNS mononuclear cell infiltration; other mannosylated peptides were ineffective in this experimental setting. Despite apparently normal T cell responses, M-PLP139-151-immunized mice show impaired delayed-type-sensitivity to PLP139-151 but a normal response to other peptides. After re-immunization with PLP139-151 in complete adjuvant, these mice are largely tolerant to EAE, show less T cell proliferation and decreased peptide-specific IgG2a. Our data suggest that M-PLP139-151 induces peptide-specific tolerance to EAE via a mechanism of deletion or impaired migration of encephalitogenic T cells.