The aim of this study was to test the hypothesis that antimicrosomal antibo
dies, found in patients with hepatitis C virus infection (HCV) before inter
feron (INF) therapy, are directed against a microsomal protein distinct fro
m the thyroperoxidase. Sera from 99 HCV patients were analysed, before INF
therapy, by ELISA and indirect immunofluorescence (IF). We confirm that ant
ithyroid microsomal antibodies (TMA) detected in HCV patients before INF th
erapy are directed against a thyroid protein other than the usual thyropero
xidase autoantigen of autoimmune thyroiditis. (C) 1999 Elsevier Science Ire
land Ltd. Ail rights reserved.