Interaction between human albumin polymers and the envelope polypeptide of hepatitis B virus (P31) containing the translation product of the pre-S2 region.

Two preparations of human serum albumin (Cohn fraction V), when subjected to high-performance liquid chromatography, were found to contain albumin polymers with molecular sizes of 35 X 10(4) daltons or greater (breakthrough fraction), as well as tetramers, trimers and dimers. They bound to the envelope polypeptide of hepatitis B virus composed of translation products of the pre-S2 region and the S gene (P31), carrying the receptor for polymerized human serum albumin, with an activity increasing in parallel with the degree polymerization.