Two minor determinants of myelin basic protein induce experimental allergic encephalomyelitis in SJL/J mice.
Experimental allergic encephalomyelitis (EAE) is an autoimmune demyelinating disease of the central nervous system (CNS) that occurs after immunization of animals with myelin basic protein (MBP). The disease is a prototype model for the study of antigen-specific T helper cell-mediated autoimmune disease. In SJL/J mice, EAE is mediated by T helper cells directed against a 40-amino acid COOH-terminal peptic fragment of mouse small MBP. To identify the minimal T cell epitopes of MBP responsible for EAE, overlapping peptides completely encompassing the epitopes within this region were synthesized. A 28-residue peptide of mouse MBP spanning residues 87-114 (pM87-114) was able to elicit both a strong T cell response and chronic relapsing disease. To better localize the T cell epitopes, shorter peptides within this region were synthesized and two overlapping peptides, pM87-98 and pM91-104, were able to induce EAE. T cell clones and bulk lymph node cell populations reactive with pM87-98 did not respond to pM91-104. However, lymph node cells reactive with pM91-104 also reacted with pM87-98, thus showing that these two peptides represent contiguous, but distinct encephalitogenic epitopes and that both these epitopes may be contained within pM87-98. In addition, pM87-114 and pM87-98 were found to be minor determinants of the total T cell response to rat and rabbit MBP. The restricted response to MBP in SJL/J mice is similar to that of the PL/J mice in that each appears to have only a single peptide region in MBP that elicits encephalitogenic T cells. However, within the region studied, there were two if not more T cell epitopes. This differs from the single encephalitogenic PL/J epitope. These findings of a single encephalitogenic peptide region with multiple T cell epitopes and the fact that encephalitogenic T cell epitopes may be subdominant have implications for the design of treatments directed at the T cell receptor-MHC-peptide epitope complex in autoimmune disease.
Kono
D H
DH
Division of Biology, California Institute of Technology, Pasadena 91125.
Urban
J L
JL
Horvath
S J
SJ
Ando
D G
DG
Saavedra
R A
RA
Hood
L
L
D000818:Animals; D001327:Autoimmune Diseases / Q000276:immunology; D002455:Cell Division; D002460:Cell Line; D002999:Clone Cells / Q000276:immunology; D004681:Encephalomyelitis, Autoimmune, Experimental / Q000276:immunology* / Q000473:pathology; D000939:Epitopes / Q000276:immunology*; D007114:Immunization; D008198:Lymph Nodes / Q000276:immunology / Q000473:pathology; D051379:Mice; D004676:Myelin Basic Protein / Q000276:immunology*; D010446:Peptide Fragments / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology
D000939:Epitopes; D004676:Myelin Basic Protein; D010446:Peptide Fragments