Analysis of complement-bound hepatitis B virus complexes by an immuno-capture polymerase chain reaction method

Hepatitis B Virus (HBV) can be present in the circulating blood either as a free virus or as a virion-immunoglobulin (Ig) complex with or without complement. However, information regarding the complement-bound HBV circulating immune complexes (CIC) in HBV-infected patients is currently not available. In the present study, we have combined immuno-capture and polymerase chain reaction (PCR) and developed a quick method of high specificity for the detection of complement-bound HBV CIC. We found that the frequency of HBV-factor B was associated with clinical types of hepatitis B (HB) but not with that of HBV-C1q. Moreover, increased frequency at P < 0.05 were found for HBV/C1q-CIC in the group with normal total bilirubin (TBIL) and for HBV/factor B-CIC in the group with positive hepatitis B e antigen (HBeAg). These findings suggest that the immuno-capture PCR (iPCR) for the detection of HBV-bound CIC is a valuable method for analysis of the composition of the immune complexes and for the understanding of host immune response and immune pathogenesis in HBV-infected individuals. In summary, iPCR is a valuable method for analysis of the composition of the immune complexes, which may provide new and valuable insights into HBV pathogenesis.