Persistent Infection of Continuous Line of Pig Kidney Cells with a Variant of the WSN Strain of Influenza A0 Virus

Abstract

RES cells were infected with the RES₁₆ variant of the WSN strain of influenza A₀ virus and the culture medium changed at frequent intervals; five lines of cells were established in which infection was sustained for periods of 126 to 146 days. Each line of persistently-infected cells showed recurring cycles of cell degeneration and repopulation; these cultures did not remain in equilibrium with the virus indefinitely, however, and ultimately degenerated.