Effect of interferon therapy on radionuclide imaging in chronic liver diseases due to HCV infection

Interferon (alpha-IFN) exerts a modulating effect on the immune system. Kupffer cells of the liver play an important immunological role by their uptake of various agents and particles, including colloids. We sought to discover if alpha-IFN could enhance the colloid uptake function of the Kupffer cells. The effect of alpha-IFN therapy on radioisotope scans of the liver was studied in 20 patients with chronic liver disease due to hepatitic C virus (HCV) infection who received therapy at a dose of 3 million IU for 6 mo, in another 20 patients who received the same therapy for 12 mo and in matched control groups (10 patients with HCV infection for each study group) who did not receive alpha-IFN.

A 99mTc-sulfur colloid scan of the liver was obtained for each group before and after therapy and, for control subjects, at the start and end of the study periods. The liver-to-spleen geometric mean ratio of colloid uptake was assessed.

In the first study group, the mean rate of improvement in the liver-to-spleen ratio was 48% in 70% of patients, compared to 8% in 20% of controls (p < 0.05). In the second study group, mean liver-to-spleen ratio was 88% in 85% of patients, compared to 12% in 40% of controls (p < 0.001).

Alpha-IFN therapy appears to enhance the colloidal uptake function of Kupffer cells, which adds a new dimension to the immunomodulatory effect of interferon.