Importance of the Infecting Dose on Growth Patterns of Rous Sarcoma Virus (RSV) in Chick Brain

Abstract

The growth curves of Rous sarcoma virus (RSV) in chick brain paralleled those of many nononcogenic animal viruses only when large doses were used. First, virus disappeared very rapidly from the brain after intracerebral inoculation. This was followed by a stationary phase of varying duration, during which the infective virus content of the brain remained low. Finally, the relative potencies of brain tissue increased logarithmically and reached their peak in moribund chicks. Growth curves were obtained for each of six different doses of RSV. It was found that the length of the stationary phase, the time to double-extractable potency, and the maximum potency attained in brain tissue were directly related to the amount of virus contained in the infecting inoculums. It is suggested that the dependence of the pathogenesis of disease on the amount of RSV contained in the infecting dose represents a basic difference between at least one tumor virus and the nononcogenic viruses.