Persistent Infection of Mouse Cells with Sindbis Virus: role of Virulence of Strains, Auto-interfering Particles and Interferon

Abstract

SUMMARY A carrier state of Sindbis virus with cycling pattern was induced in the mouse L cells and in the established mouse embryo cell line MEC/c. Chick-adapted virus readily induced the persistent infection whereas the mouse-adapted virus killed cultures during the first passage. In the MEC/c line small (sp) and large (lp) plaque mutants of Sindbis virus produced more stable carrier state than the giant (gp) plaque mutant. The persistently infected cultures periodically produced small amounts of interferon. Highly specific rabbit anti-interferon globulin, which can neutralize mouse interferon, incorporated into the growth medium of carrier L line caused a 100- to 1000-fold stimulation of the synthesis of Sindbis virus after incubation for 5 days at 37 °C. The activated virus destroyed the carrier culture.