EFFECT OF ALPHA-INTERFERON ON NATURAL-KILLER-CELL ACTIVITY AND LYMPHOCYTE SUBSETS IN THALASSEMIA PATIENTS WITH CHRONIC HEPATITIS-C

The variation of natural killer (NK) cell activity and lymphocyte subs ets 20 h after a single test dose of alpha-IFN, was studied in 17 thal assemic patients with chronic hepatitis C. All patients had suspended the alpha-IFN therapy at least 12 months before the study: 10 were con sidered responders and 7 nonresponders. Also NK cell cytotoxicity afte r in vitro incubation with alpha-IFN was studied. The administration o f a single dose of alpha-IFN increased NK cell cytotoxic activity sign ificantly in the group of responders and in non-responders; moreover t he NK cell cytotoxic activity after alpha-IFN in vitro incubation incr eased both in responders and nonresponders, but to a lesser degree tha n in healthy controls. Absolute values of CD4+ and CD8+ lymphocytes de creased significantly only in responders. In conclusion, our data sugg est that the variation of NK cytotoxic activity and lymphocyte subsets after a test dose of alpha-IFN can be considered a parameter related to IFN biological effects.