SUMMARY
γδ T cells are a subset of T cells with unknown function, and restriction of the γδ T cell receptor (TCR) repertoire has been described in rheumatoid arthritis and multiple sclerosis. Elevated numbers of γδ cells have been reported in the peripheral blood and thyroids of patients with Graves' disease. We have carried out flow cytometric analysis on peripheral blood mononuclear cells (PBMC) and intrathyroidal lymphocytes (ITL) from 12 patients with Graves' disease and nine patients with multinodular goitre (MNG). a thyroid disease of unknown etiology. There was no significant difference between the proportion of γδ T cells in the PBMC of Graves' and MNG patients, nor between the PBMC and ITL populations in either patient group. We have also carried out polymerase chain reaction amplification on RNA prepared from matched PBMC. ITL and the activated (CD25+) subset of ITL using six TCR γδ‐family specific primers. Although there were differences in the amounts of each γδ transcript amplified from PBMC and ITL, there was no difference between the two patient groups. No consistent differences were therefore found between the γδ T cell populations in Graves' and MNG patients, arguing against the direct involvement of this T cell subset in the pathogenesis of Graves' disease.