The autoreactive T cell population in experimental allergic encephalomyelitis: T cell receptor beta-chain rearrangements.

T cell receptor beta-chain gene rearrangements were examined in myelin basic protein (MBP)-reactive T cell lines and hybridomas from Lewis (Lew) rats. Nearly 75% of the cloned hybrids were specific for the major encephalitogenic determinant residues 68-88 of guinea pig (GP) MBP; three fine specificities could be distinguished. Southern blot analysis of receptor beta-chain genes revealed polyclonality and shared rearrangements not seen in non-68-88-specific clones. Generation of short-term, encephalitogenic Lew T cell lines revealed rearrangements shared with the 68-88-specific hybrids, indicating that the hybrids were representative of the whole antigen-specific population and suggesting restricted V beta gene usage within this polyclonal population.