Albumin interaction with HBsAg as one of the possible sources of the polyethylene glycol "immune complexes" turbidity in hepatitis B.

The reported discrepancies between detection of the circulating immune complexes (CIC) by complement activation markers and by polyethylene glycol (PEG) turbidity tests suggested the possibility that PEG turbidity in hepatitis B is formed not only by HBsAg-immunoglobulin CIC but also by complexes formed on interaction of HBsAg with polymerized albumin. This hypothesis is supported by a correlation of HBsAg with the presence of albumin in the turbidities isolated from HBsAg positive and negative sera by the same procedure by which CIC had been detected. The existence of several sources of PEG turbidity specific for hepatitis B, e. g. HBeAg/anti-HBe; albumin/HBsAg; and others makes these methods most appropriate for screening blood donors and testing for residual abnormalities in sera from apparently normal people.