The Purification and Concentration of Viruses and Virus Soluble Antigens on Calcium Phosphate

Abstract

Chromatography on columns of calcium phosphate has been used to purify and concentrate viruses and their related soluble antigens. The method is an adaptation of one which has already proved successful with proteins and other large molecules. An important advantage is that all operations are carried out at pH 7, elution being effected by alterations in phosphate concentration. The PR8 strain of influenza was used as a model. Chromatrog-raphy on a calcium phosphate column effected a 30- to 100-fold increase in purity, with a recovery of 50-80%. By chromatography on a second small column a 10- to 30-fold concentration could be obtained; little further purification occurred. Material with a purity up to 10[degree] haemagglutination units/mg protein was obtained; this compares favorably with material purified by other methods. PR8 soluble antigen was similarly purified and concentrated, and Semliki forest virus was also purified. In preliminary experiments, purification of vaccinia, encephalomyocarditis, Coxsackie and poliomyelitis type III viruses has also been effected. The method is simple and rapid and can be used with crude virus suspensions from different sources. The viruses retained both their infectivity and their antigenicity as judged by complement fixation.