Gamma delta T cell receptor variable region usage during the development of experimental allergic encephalomyelitis

The molecular diversity of gamma delta T cells has not previously been investigated in experimental allergic encephalomyelitis (EAE). This study characterised the gamma delta T cell receptor (TCR) variable (V) region repertoires of T cells infiltrating the brains of EAE mice during development of the disease. TCR gamma- and delta-specific cDNAs were synthesised from total RNA prepared from brain samples and transcription of rearranged V genes was assessed by polymerase chain reaction amplification of TCR V-C transcripts and Southern blot analysis. In the early stages of EAE, the TCR gamma-chain repertoire consisted of V gamma 1-3 and V gamma 6 transcripts and, similarly, a few V delta transcripts that used primarily V delta 1, V delta 4 and V delta 5 gene segments were detected. During the progression of EAE, however, most V gamma and V delta TCR transcripts were observed in the brain. These results indicate that in the course of murine EAE there is an initial infiltration into the brain of a restricted population of gamma delta T cells followed by a heterogeneous gamma delta TCR repertoire as the disease develops. Moreover, the data suggest that gamma delta T cells may play a role in the pathogenesis of demyelinating autoimmune disease.