Eluding anaphylaxis allows peptide-specific prevention of the relapsing stage of experimental autoimmune encephalomyelitis

Abstract We have used a peptide derived from Acanthamoeba castellanii (ACA) to treat the relapsing phase of EAE that develops in SJL mice following immunization with the PLP 139–151 peptide. The native sequence of the ACA 81–95 peptide that shares key residues with the PLP 139–151 peptide is weakly encephalitogenic in SJL mice but is not recognized by antiserum from SJL mice immunized with PLP 139–151. A single amino acid change to the ACA 81–95 peptide sequence significantly enhanced its encephalitogenicity. When administered to SJL mice as a nonlinear peptide octamer, the modified ACA peptide prevented relapsing episodes of EAE in SJL mice previously immunized with the PLP 139–151 encephalitogenic peptide.