Characterization of circulating immune complexes in chronic non-A, non-B hepatitis

We studied the frequency and composition of circulating immune complexes (CIC) in patients with chronic persistent non-A, non-B (NANB) hepatitis and in convalescent persons after an apparently normal recovery from acute NANB hepatitis. 10 of 16 patients with chronic NANB hepatitis and 5 of 11 convalescent persons after acute NANB hepatitis had CIC as detected by the Raji cell technique. CIC in chronic NANB hepatitis were composed of IgG, C3, and in 7 of 10 cases also IgM, while in CIC from convalescent persons IgG and C3 were present, too, but IgM was detected in only 1 case. Viral antigens within the CIC were not detectable in any case while 14 of 16 chronic NANB hepatitis patients were found to have free virus-associated antigen in serum.