Hepatitis B surface antigen polypeptide micelles from antigen expressed in Saccharomyces cerevisiae.

Hepatitis B micelles containing the p25 component of hepatitis B surface antigen (HBsAg) have been produced by Triton X-100 solubilization followed by ultracentrifugation in linear sucrose gradients. The product was found to resemble micelle forms prepared from plasma-derived HBsAg with the surface being composed of discrete globular and stranded sub-units. The degree of immunochemical relatedness of the micellular preparation was compared to the native 22-nm HBsAg particle present in either plasma or yeast cell extracts. The yeast micelle preparation competed for anti-HBs in a similar manner as intact HBsAg of plasma origin. Enhanced immunogenicity may be expected for micelles containing a recombinant HBsAg protein as has previously been shown for the plasma-derived antigen.