/T-cells might play an important role in autoimmune conditions like inflammatory bowel disease. In the present study we characterized the TCR- repertoire by CDR3-spectratyping in the inflamed and non-inflamed mucosa and in the peripheral blood of subjects with Crohn's disease and ulcerative colitis. In contrast to previously published data about /ßT-cells we rarely found oligoclonal expansions of /T-cells which were specific only for the inflamed mucosa. The same dominant /T-cell expansions were also present in the non-inflamed colon. Furthermore, the peripheral /TCR-repertoire was oligoclonal but clearly distinct from that in the inflamed intestine. Thus, our results do not support a role for antigen specific /T-cells in IBD, and dominant /T-cells of the peripheral blood are not likely to be derived from the inflamed gut. However, in several patients the TCR--repertoire was highly diversified whereas in others we observed a loss of dominant /T-cell clones when inflamed and non-inflamed mucosa were compared. In conclusion, those changes indicate that /T-cells might play an important role in a subset of patients with IBD.