A double mutation of MBP83-99 peptide induces IL-4 responses and antagonizes IFN-? responses

Abstract

A number of treatment options are available to multiple sclerosis patients, however this needs to be improved. Herein, we designed and synthesized a number of peptides by mutating principal TCR contact residues based on MBP83-99 peptide epitope. Immunization of SJL/J mice with MBP83-99 and mutant [A91]MBP83-99, [E91]MBP83-99, [F91]MBP83-99, [Y91]MBP83-99, and [R91, A96]MBP83-99 peptides, induced IFN-?, and only [R91, A96]MBP83-99 mutant peptide was able to induce IL-4 secretion by T cells. T cells against the native MBP83-99 peptide cross-reacted with all peptides except [Y91]MBP83-99 and [R91,A96]MBP83-99. The double mutant [R91, A96]MBP83-99 was able to antagonize IFN-? production in vitro by T cells against the native MBP83-99 peptide. Antibodies generated to [R91, A96]MBP83-99 did not cross-react with whole MBP protein. Molecular modeling between peptide analogs and H2 I-As demonstrated novel interactions. The [R91, A96]MBP83-99 double mutant peptide analog is the most promising for further therapeutic studies. © 2008 Elsevier B.V. All rights reserved.