INFILTRATING GAMMA DELTA T-CELL RECEPTOR-POSITIVE LYMPHOCYTES IN HASHIMOTOS-THYROIDITIS, GRAVES-DISEASE AND PAPILLARY THYROID-CANCER/

In the present study we have evaluated the expression of different mol ecular forms of the antigen receptor (TcR) on lymphocytes derived from thyroid tissue of patients with Graves' disease, Hashimoto thyroiditi s and papillary cancer both in situ by APAAP technique and on isolated lymphocytes by indirect immunofluorescence. A panel of monoclonal ant ibodies (mAbs) recognizing alpha/beta and gamma/delta TcR-positive maj ority of T-cells in thyroid infiltrates were alpha/beta TcR+, gamma/de lta TcR+ ones being very rare or nearly absent, whatever the disease ( autoimmune or neoplastic). No difference between gamma/delta TcR+ T-ce ll subsets (V delta 1+ or V delta 2+) was observed. Thus, neither in a utoimmune thyroid diseases nor in papillary cancer gamma/delta TcR+ ce lls are likely to be a major effector-T cell population.