CHROMATOGRAPHY OF POLIOVIRUS ON CALCIUM PHOSPHATE AND ITS APPLICATION TO THE IDENTIFICATION OF VACCINE PROGENY STRAINS.

Ozaki, Yoshikatsu (Baylor University College of Medicine, Houston, Tex.), Arwin R. Diwan, Mizuho Takizawa, and Joseph L. Melnick. Chromatography of poliovirus on calcium phosphate and its application to the identification of vaccine progeny strains. J. Bacteriol. 89:603-610. 1965.-Virulent and attenuated polioviruses were studied chromatographically with calcium phosphate as adsorbent and neutral phosphate buffer as eluent. For type 1, the attenuated LSc2ab strain and the virulent Mahoney strain were eluted at different salt concentrations. The peak of elution for the LSc2ab strain was at 0.3 m, whereas for the Mahoney strain it was at 0.05 m. No differences in elution pattern were noted with virulent and attenuated strains of poliovirus types 2 and 3. Except for a single instance, progeny strains isolated from vaccines or contacts 1 to 8 weeks after vaccination showed an elution pattern similar to the parent vaccine strain, or intermediate between the virulent and attenuated strains but still clearly distinguishable from wild-type virus. A virus population that possessed the same elution property as the virulent Mahoney strain could be separated from a number of progeny strains by chromatography. The ratio of this easily eluted population appeared to increase during the course of multiplication of vaccine virus in the human intestine. A virus population with the same elution profile as Mahoney seems to be present in the current LSc2ab oral polio vaccine, but as a very minor component. However, this component could readily be enriched by selecting for passage only those virus particles eluted at low salt concentrations. Heat-resistant, attenuated virus strains were selected from virulent type 1 strains by the Wallis-Melnick procedure of repetitive heating of progeny in AlCl(3). However, the elution pattern remained the same as that of the parent virulent virus.