EVIDENCE OF HTLV-I IN THYROID-TISSUE IN AN HTLV-I CARRIER WITH HASHIMOTOS-THYROIDITIS

Human T-lymphotropic virus type I (HTLV-I) protein and messenger RNA ( mRNA) for HTLV-I were examined in thyroid tissues from two patients wi th Hashimoto's thyroiditis and serum anti-thyroid antibody. The virus envelope protein and signals for the mRNA were detected in many of the follicular epithelial cells of the thyroid tissue from one of the pat ients, respectively, by immunohistochemistry and in situ hybridization . PCR-Southern blotting revealed the presence of HTLV-I DNA in the thy roid tissue, in which the viral protein and mRNA were detected, althou gh no virus particles were found in the epithelial cells by electron m icroscopy. HTLV-I virus was not present in the thyroid tissue from the second patient, The present findings suggest that infection of thyroi d tissue with HTLV-I is associated with the pathogenesis of Hashimoto' s thyroiditis in some patients.