Detection of hepatitis C virus RNA in circulating immune complexes by RT-PCR

Background/Aims : We investigate whether hepatitis C virus (HCV) forms a circulating immune complex (CIC) in patients with chronic HCV infection. Materials and Methods : We examined HCV-RNA immunoprecipitated with anti-human IgG, A and M antibodies by reverse transcription-polymerase chain reaction. Results : In thirty-nine (91%) of 43 patients, composed of 35 chronic hepatitis (CH) and 8 liver cirrhosis (LC), HCV-RNA was detected in the CIC. All 43 patients analyzed were classified into the following three categories ; HCV-RNA was detected only in the supernatant (S pattern, 4 patients), both in the supernatant and the precipitate (SP pattern, 27 patients), and only in the precipitate (P pattern, 12 patients). SP pattern was most common in chronic HCV infection, and the frequency of SP pattern decreased with the progression of liver disease. P pattern was significantly more frequent in patients with higher γ-globulin levels, histologically indicated LC, and antibody to HCV envelope protein. Conclusion : We found that HCV formed a CIC in most patients with chronic HCV infection, and that the formation of CIC might be related to the stage of chronic HCV infection.