Route of uptake of palmitoylated encephalitogenic peptides of myelin proteolipid protein by antigen-presenting cells: importance of the type of bond between lipid chain and peptide and relevance to autoimmunity.

Previously, we have shown that thiopalmitoylation of peptides of myelin proteolipid protein, as occurs naturally in vivo, increases their ability to induce experimental autoimmune encephalomyelitis, the animal model of multiple sclerosis, and skews the autoimmune response toward a CD4(+)-mediated response. In contrast, the same peptide, when synthesized with a stable amide bond between peptide and lipid, inhibits experimental autoimmune encephalomyelitis and skews the response toward a CD8(+) response. The aim of the current study was to determine the mechanisms responsible for these observations.