Abstract: There are disclosed a process for enhancing the immunogenicity of a lipid membrane based immunogen comprising flash heating it at a membrane concentrations sufficient under the conditions of flash heating to result in melting of membranes and fusing the melted membranes into novel morphologic forms and a proteinaceous mass comprising particles of HBsAg, said particles including particles of HBsAg in morphologic form not found in nature, said HBsAg contains particles being filaments, branched filaments, closed circular or closed circular branched filaments.

Abstract: There is disclosed a new synthetic peptide which evokes an immunological response. The synthetic peptide, moreover, interacts with antibodies to hepatitis B surface antigen (HBsAg). Thus, the synthetic peptide is useful as an immunizing agent in a vaccine as an active component thereof where it serves to produce antibodies in vivo which are protective against hepatitis B virus. The synthetic peptide of the invention comprises the following sequence of amino acids: Arg Trp Met Met Leu Arg Arg (I) and preferably has the following sequence: Gly Tyr Arg Trp Met Met Leu Arg Arg Phe Gly (II).

Abstract: There is disclosed a new synthetic peptide which evokes an immunological response. The synthetic peptide, moreover, interacts with antibodies to Hepatitis B surface antigen (HBsAG). Thus, the synthetic peptide is useful as an immunizing agent in a vaccine as an active component thereof where it serves to produce antibodies in vivo which are protective against Hepatitis B virus. The synthetic peptide of the invention comprises the following sequence of amino acids: Arg Trp Met Met Leu Arg Arg(I) and preferably has the following sequence: Gly Tyr Arg Trp Met Met Leu Arg Arg Phe Gly (II).

Abstract: A vaccine against viral hepatitis comprising:A. antigenic particles having a particle size in the range of 30 to 50 nanometers, said antigenic particles containing hepatitis B surface antigens;B. said antigen having less than 10 units of free antibody to hepatitis B surface antigens per 1,000 units of hepatitis B surface antigens;C. at least 5% of the particles of said vaccine in the size range of 30 to 50 nanometers containing the hepatitis B surface antigenic specificity(s) which have been termed "e-antigen";D. said hepatitis B surface antigens, including e-antigens, being present in said vaccine in an amount sufficient to produce antibodies when introduced into a host animal, the balance being a medium which is physiologically acceptable, especially to humans and primates.

Abstract: A process for preparing a vaccine containing unprecipitated filaments and hepatitis B Dane particle specific antigens by removal from a blood serum of other proteinaceous matter such that the serum contains less than 10% proteinaceous matter other than that associated with hepatitis B surface antigen or the filament or Dane particle specific antigen. Any virus present is inactivated, and the antigenous mass is diluted with a physiologically acceptable medium.

Abstract: A vaccine against viral heptitis comprising:A. antigenic particles having a particle size in the range of 30 to 50 nanometers, said antigenic particles containing heptitis B surface antigens;B. said antigen having less than 10 units of free antibody to heptitis B surface antigens per 1,000 units of hepatitis B surface antigens;C. at least 5% of the particles of said vaccine in the size range of 30 to 50 nanometers containing the hepatitis B surface antigenic specificity(s) which have been termed "e-antigen";D. said heptatis B surface antigens, including e-antigens, being present in said vaccine in an amount sufficient to produce antibodies when introduced into a host animal, the balance being a medium which is physiologically acceptable, especially to humans and primates.

Abstract: Highly purified type B hepatitis antigen (HB Ag) is produced from fluid blood material containing such antigen by subjecting blood material containing naturally occurring HB Ag to a double precipitation with polyethylene glycol. In each precipitation, the pH of the fluid blood material is maintained at approximately 4.4 to 4.7 and a polyethylene glycol concentration of approximately 4.0 to 4.5 weight per cent is used. Particularly good results are obtained if the temperature of the material is maintained in the range of 0.degree. to 8.degree.C after the polyethylene glycol has been added. The antigen thus obtained may be further purified by absorption of impurities to hydroxy apatite, followed by isopycnic banding and zonal ultracentrifugation. Hydroxy apatite column chromatography is used to separate the purified antigen into three separate populations of particles.