Detection and characterization of circulating immune complexes during acute exacerbation of chronic viral hepatitis.

For detection and characterization of circulating immune complexes (CIC) in various liver diseases, a C1q binding test (C1q BT) was used. While the CIC level was almost normal in HB surface antigen (HBsAg) positive asymptomatic carriers, it was relatively high in patients with liver diseases. The study of the sedimentation rate of CIC in various liver diseases showed two kinds of CIC; one greater than the other. During acute exacerbation of chronic active liver diseases, the CIC level reached its peak 1-5 weeks before and after the peak of sGPT. In acid buffer, CIC in one patient with HBsAg positive severe chronic aggressive hepatitis was dissociated into 5-6 fractions by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The two of these fractions proved to be HBsAg and IgG and another three or four undetermined components. At the acute exacerbation period of this case, the fraction pattern of CIC by SDS-PAGE was similar to each other at any of the four stages and HBsAg always composed one of the antigens.