SIZE-EXCLUSION CHROMATOGRAPHY OF HEPATITIS-B SURFACE-ANTIGEN PARTICLES

To find the factors responsible for the broadening of the recombinant- hepatitis B surface-antigen peak in size-exclusion chromatography, the purified material was fractionated on preparative scale followed by m ultiple analysis of the separated fractions. The results from chromato graphic analysis suggested the presence of large particle aggregates, probably tubular structures which, however, were not detected by elect ron microscopy. The antigen particles ranged from 16 to 32 nm in all t he fractions, except two last fractions consisting of 16-24 nm particl es. The relation ELISA/Lowry increased with increasing the fraction nu mber, being a maximum in the fraction corresponding to the maximum of the chromatographic peak. Probably, the particles which are variable i n size differ from each other with respect to the efficiency of protei n assembly. Fractions collected in different regions of the peak were adsorbed on alum and injected in mice. The high antibody levels were p roduced without significant differences in immunogenicity between samp les.