IN SUBJECTS WITH ANTIBODY TO HEPATITIS-C VIRUS A HIGH SERUM LEVEL OF INTERLEUKIN-2 SOLUBLE RECEPTOR SUGGESTS ACTIVITY OF LIVER-DISEASE

The hepatitis C virus (HCV) is an RNA virus without apparent cytopathi c effects, and hepatocellular damage in chronic infection is generally believed to be immune-mediated by cytotoxic T lymphocytes. Activated T cells release the soluble form of the interleukin-2 (IL-2) receptor (sIL-2R) and its concentration is correlated with the degree of lympho cyte activation, We measured sIL-2R in 69 subjects: 24 healthy repeat blood donors (group I), 17 HCV carriers without liver damage (group II ) and 28 patients with HCV-related chronic active hepatitis (group Ill ). There was no significant difference between sIL-2R levels in patien ts of group I (36.5 +/- 14.6 U ml(-1)) and group II (46.8 +/- 17.4 U m l(-1)), and the levels for both of these groups were significantly low er than those observed in the patients with active HCV, group III (176 .9 +/- 59.5 U ml(-1)). Hence, among HCV-infected subjects (HCV RNA pos itive) with persistently normal alanine aminotransferase (ALT) levels, the plasma levels of sIL-2R are normal, but, in patients (HCV RNA pos itive) with HCV-related chronic active hepatitis there are increased p lasma levels of sIL-2R. We conclude that in HCV infection high levels of sIL-2R are related to activity of the disease rather than to virus replication. In patients with HCV-related chronic liver disease, the s IL-2R concentration may be a useful marker of disease activity.