Hepatitis-Associated Australia Antigen. Protein, Peptides and Amino Acid Composition of Purified Antigen with Its Use in Determining Sensitivity of the Hemagglutination Test

Abstract

Summary: A 0.1% solution of protein from the purified 20-nm particles of hepatitis-associated Australia antigen (HAA) has an optical density of 3.726 at 280 nm. The protein appears to consist of two subunits; it contains a high proportion of proline, leucine and serine and a low content of tyrosine. Depending upon the anti-HAA reagent used, the hemagglutination inhibition assay can detect HAA protein in amounts as low as 1 to 60 ng.