Immunochemical Studies of Poliovirus: II. Kinetics of the Formation of Infectious and Noninfectious Type 1 Poliovirus in Three Cell Strains of Human Derivation

Abstract
The cellular materials and extracellular fluids from cultures of 3 cell strains of human derivation were assayed for viral substances throughout a period of 15–19 hr following high multiplicity infection with Type 1 poliovirus. Infectivity measurements were done by the plaque technique, and assays for C and D antigens were made by complement fixation. During the first 10–12 hr following seeding, infectious virus, as well as the C and D antigens, were found to accumulate in the cellular fraction. Significant amounts of viral material appeared in the extracellular fluid only after this period of accumulation. It was found that 100,000 to 500,000 physical poliovirus particles (PVP) are produced/cell. This datum is derived from D antigen titers which were converted to PVP by use of the previously established relationship between D antigen and PVP. The 3 cell lines were found to differ in the quantity of virus produced/cell, and in the proportion of virus particles that are infectious. C antigen was found in both cellular and extracellular material.