Mannosylated Linear and Cyclic Single Amino Acid Mutant Peptides Using a Small 10 Amino Acid Linker Constitute Promising Candidates Against Multiple Sclerosis.

Stephanie Day,Theodore Tselios,Anthi Tapeinou,Irene Frilligou,Maria-Eleni Androutsou,Lily Stojanovska,Vasso Apostolopoulos,John Matsoukas

doi:10.3389/fimmu.2015.00136

Stephanie Day, Theodore Tselios + Show 6 more

Open Access

https://doi.org/10.3389/fimmu.2015.00136

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Abstract

Multiple sclerosis (MS) is a serious autoimmune demyelinating disease leading to loss of neurological function. The design and synthesis of various altered peptide ligands of immunodominant epitopes of myelin proteins to alter the autoimmune response, is a promising therapeutic approach for MS. In this study, linear and cyclic peptide analogs based on the myelin basic protein 83–99 (MBP83–99) immunodominant epitope conjugated to reduced mannan via the (KG)5 and keyhole limpet hemocyanin (KLH) bridge, respectively, were evaluated for their biological/immunological profiles in SJL/J mice. Of all the peptide analogs tested, linear MBP83–99(F91) and linear MBP83–99(Y91) conjugated to reduced mannan via a (KG)5 linker and cyclic MBP83–99(F91) conjugated to reduce mannan via KLH linker, yielded the best immunological profile and constitute novel candidates for further immunotherapeutic studies against MS in animal models and in human clinical trials.

Highlights

Multiple sclerosis (MS) is often a slowly progressive and chronic auto-immunologically mediated disease of the central nervous system (CNS), with inflammation around the myelin sheath [1,2,3]
In a human phase II clinical trial in MS patients, substitution of the epitope MBP83–99, with several d-amino acids or Ala at the N terminal (NBI-5788, CGP77116) induced strong IL-5 and IL-13 cytokine responses; many patients developed dangerous side effects and the clinical trials were stopped [17, 18]. These results indicated that further pre-clinical testing is required and new modified peptides need to be designed together with appropriate immunomodulatory adjuvants or carriers, for the peptide based immunotherapeutic approaches against MS
We previously demonstrated that linear and cyclic substituted APLs based on MBP83–99 and MBP87–99 epitopes, with single or double mutations at positions 91 and 96 as being the crucial TCR contact residues, conjugated to reduced mannan via the keyhole limpet hemocyanin (KLH) as a linker diverts the

Summary

INTRODUCTION

Multiple sclerosis (MS) is often a slowly progressive and chronic auto-immunologically mediated disease of the central nervous system (CNS), with inflammation around the myelin sheath [1,2,3]. Frontiers in Immunology | Multiple Sclerosis and Neuroimmunology immune response from Th1 to Th2 enhancing the induction of anti-inflammatory cytokines IL-4 and IL-10 [30,31,32,33,34,35] In these studies, the cyclic and linear APLs were conjugated to KLH followed by conjugation to oxidized mannan and followed by its reduction to result in reduced-mannan conjugates. The use of a smaller bridge like (KG) rather than KLH could potentially reduce antibody responses against the immunizing peptide, which could otherwise be a problem in human clinical trials In this respect, a number of APL analogs with (KG) at its N-terminus and conjugated to reduced. Mannan were studied in SJL/J mice for their ability to induce immune responses, especially, T cell proliferation, IFN-gamma, IL-4, and IL-10 cytokine secretion and antibody responses

RESULTS AND DISCUSSION

CONCLUSION

EXPERIMENTAL PROCEDURES