Clonal diversity of myelin basic protein-specific T lymphocytes

A panel of myelin basic protein (MBP)-specific, class II major histocompatibility complex (A^s)-restricted T-cell clones were established from SJL/J mice. Three clonotypes, based on their responses to guinea pig MBP and its peptide fragments, were observed. Clonotype I cells, represented by clones HS.6, HS.D2, HS.8, HS.E10, and HS.C1, were reactive to the encephalitogenic C-terminal fragment of MBP, amino acid residues 89-169. Clonotype II, represented by clone HS.E3, was reactive to fragments containing residues 43-88, and clones HS.D12 and HS.C7, representing clonotype III cells, responded to the whole molecule only. Three clones from clonotype I were capable of transferring both clinical and histological signs of experimental allergic encephalomyelitis (EAE) into naive mice. Southern blot analysis of T-cell receptor β-chain genes using J_β1- and J_β2-specific probes showed that the rearrangement pattern was unique in each of the clones. These results suggest that the development of EAE may represent an autoaggressive polyclonal T-cell response.