THE IMMUNE-RESPONSE TO A SUBDOMINANT EPITOPE IN MYELIN BASIC-PROTEIN EXON-2 RESULTS IN IMMUNITY TO INTRAMOLECULAR AND INTERMOLECULAR DOMINANT EPITOPES

Experimental autoimmune encephalomyelitis was induced in SJL/J mice by adoptive transfer of a MBP exon-2 peptide-specific T cell line. The T cell line, when tested for antigen specificity, reacted strongly with exon-2 peptide, but not with MBP peptides pAcl-11, p43-88, p89-101 or PLP p139-151. The specificity of splenic or lymph node T cells isolat ed from mice with acute or first relapse EAE induced by adoptive trans fer of the exon-2-specific T cell line was identical to the transferre d line. Splenocytes or lymphocytes isolated from mice at the second re lapse were reactive with MBP p43-88, p89-101 and PLP p139-151 in addit ion to exon-2 peptide and MBP peptide Acl-11. T cell lines selected by culture with MBP exon-2 peptide or PLP p139-151 from splenic cells fr om mice with relapsing EAE were weakly encephalitogenic; however, T ce ll lines selected from the same mice with MBP pAcl-11 were not encepha litogenic. T cells from the exon-2 and p139-151 T cell lines primed re cipients for rapid onset severe EAE, whereas the pAcl-11 T cell line d id not. T cells from the exon-2-specific line did not express V(beta)1 7a(+) TCR; however, peptide-specific T cell lines derived from the spl eens of relapsing animals did express this TCR gene segment providing direct evidence of recruitment and sensitization of recipient T cells.