Determination of e antigen and antibody to e by means of passive hemagglutination method.

A simple and sensitive method was developed for the detection of e antigen and antibody to e (anti-e) by means of the passive hemagglutination (PHA) method. Sheep erythrocytes were fixed by glutraraldehyde and coated with either e antigen or anti-e which had been specifically purified from plasma of asymptomatic carriers of hepatitis B antigen by affinity column chromatography, and then by gel filtration on Sephadex G-200. A gain in specific activity of more than 2000-fold for e antigen and 100-fold for anti-e was achieved as compared with the original plasma pool which was used as the source for purification. The PHA method was at least 300 times more sensitive than the conventional immunodiffusion method both for e antigen and anti-e assays. When the PHA method was applied for neat serum samples of 80 asymptomatic carriers, e antigen was found in 21.3% and anti-e in 62.5%, at rates much higher than those determined by immunodiffusion for the identical serum samples at 3-fold concentration (16.3 and 30.0%, respectively).