ANTISERUM INHIBITION OF PROPAGATING VIRUSES

The design and implementation of controlled environments to continuous ly culture and evolve viruses provides a means to track how their popu lations respond to natural and designed anti-viral agents. We have pre viously demonstrated how the growth of viruses in spreading plaques en ables detection and characterization of their evolutionary dynamics. U sing plaques of phage T7 growing on E. coli as a model system, we obse rve here that velocities of propagation can be readily controlled by t he level of anti-viral antiserum incorporated into the propagation med ium. Further, we develop a simple analytic expression for the radial v elocity of propagation in terms of the microscopic rates of viral ampl ification, Fickian diffusion of the virions and their neutralization b y antiserum. Our analysis captures the essential dependence of propaga tion velocity on antiserum concentration. This study provides an ex vi vo foundation for exploring how medically relevant viruses escape supp ression by the immune system. (C) 1997 John Wiley & Sons, Inc.