Selection for T-cell receptor Vβ–Dβ–Jβ gene rearrangements with specificity for a myelin basic protein peptide in brain lesions of multiple sclerosis

Abstract

MULTIPLE sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system in which a restricted cellular immune response has been observed. In order to establish whether such T cell responses are likely to be antigen-specific particularly with regard to myelin basic protein (MBP), we analysed T-cell receptor (TCR) gene rearrangements directly from MS brain plaques, using the polymerase chain reaction on reverse transcribed messenger RNA, and compared these with TCR of previously described MBP-specific T cell clones from MS and the rat model experimental allergic encephalomyelitis. Rearranged Vβ5.2 genes were detected in the brains of all patients who were HLA DRB1^*1501, DQA1^*0102, DQB1^*0602, DPB1^*0401. The Vβ5.2–Dβ–Jβ sequences in these MS brain plaques revealed five motifs. One of the common motifs was identical to that described for the VDJ region of a Vβ5.2 T-cell clone. This clone was from an MS patient who was HLA DRB1^*1501, DQB1^*0602, DPB1^*0401, and it was cytotoxic towards targets containing the MBP peptide 89–106 (ref. 1). The deduced amino-acid sequence of this VDJ rearrangement, Leu-Arg-Gly, has also been described in rat T cells cloned from experimental allergic encephalomyelitis lesions, which are specific for MBP peptide 87–99 (ref. 2). VDJ sequences with specificity for this MBP epitope constitute a large fraction (40%) of the TCR Vβ5.2 N(D)N rearrangements in MS lesions. The capacity of rat T cells with these VDJ sequences to cause experimental allergic encephalomyelitis² and the prevalence of such sequences in demyelinated human lesions indicate that T cells with this rearranged TCR may be critical in MS.