Elevated levels of 2',5'-oligoadenylate synthetase activity in peripheral blood mononuclear cells and serum during acute exacerbation of chronic hepatitis B.

We measured 2',5'-oligoadenylate synthetase activity in peripheral blood mononuclear cells and serum of 14 HBsAg- and HBeAg-positive patients with chronic hepatitis B with or without acute exacerbation. Elevated levels of 2',5'-oligoadenylate synthetase in peripheral blood mononuclear cells and serum were found in seven chronic hepatitis B patients with acute exacerbation, whereas in the remaining seven chronic hepatitis B patients without acute exacerbation, both levels were similar to those of normal subjects despite active hepatitis B virus multiplication. 2',5'-Oligoadenylate synthetase levels in peripheral blood mononuclear cells and serum, which were not statistically different from those of normal subjects prior to acute exacerbation, increased during acute exacerbation from 3- to 23-fold over initial levels following elevations in ALT activity. 2',5'-Oligoadenylate synthetase levels fluctuated over a normal range while ALT levels were elevated, and they returned to a baseline with ALT normalization. This suggests that the in vivo interferon system may be activated during acute exacerbation, and that this activation may not be a result of hepatitis B virus multiplication alone, but also of a host-immune response to hepatitis B virus multiplication. Three patients were treated with interferon during acute exacerbation. All three had elevated levels of 2',5'-oligoadenylate synthetase in peripheral blood mononuclear cells and serum just before treatment. 2',5'-Oligoadenylate synthetase levels increased only 1.1- to 2.2-fold over initial levels during treatment, with none of the patients clearing HBeAg during and after treatment.(ABSTRACT TRUNCATED AT 250 WORDS)