Quantitative study of the formation of poliovirus antigens in infected HeLa cells² 2 Abbreviations employed: RNA = ribonucleic acid; PFU = plaque-forming unit; FPA =dl-p-fluorophenylalanine.

Methods based on the specific interaction between isotopically labeled poliovirus antigens and their specific antisera have been used to study the course of antigen formation in infected HeLa cell cultures. No appreciable amounts of either D antigen or C antigen are formed prior to the onset of maturation. While D antigenicity is a property of structurally complete particles, C antigenicity is associated with particles which lack RNA. Both sorts of particles are primary products of the infectious process, being formed in roughly equal amounts along the course of maturation. Appreciable amounts of both antigens are formed in the presence of low concentrations of fluorophenylalanine (FPA) which inhibit infectious virus production but permit formation of infectious RNA; antigen and infectious RNA formation are inhibited at higher concentrations of FPA. The results are in accord with previous conclusions that there is close temporal, and perhaps functional coordination between viral protein and viral RNA synthesis in this system.