Recombinant gamma-interferon stimulates iodide uptake and cyclic AMP production by the FTRL5 thyroid cell line

The effect of recombinant rat gamma-interferon (gamma-IFN) on iodide uptake and cAMP production by rat thyroid cells in vitro was studied using the continuously growing, functional FRTL5 cell line. Both functions were stimulated by gamma-IFN at concentrations of 1-10 U/ml. Iodide uptake was dependent on protein synthesis, since it was blocked by cycloheximide treatment, but was not dependent on growth factors in calf serum routinely used for FRTL5 cell culture. These results show that gamma-IFN can stimulate thyroid cell function as well as aberrant Ia expression in vitro.