Enhancement of Oncolytic Effect of Russian Encephalitis Virus.

Abstract

By continuous and prolonged passage of the virus of Russian encephalitis in mouse brain, the transplantable mouse tumor sarcoma 180 and the Wagnar osteogenic sarcoma, 3 variant strains of the parent virus were produced. They were shown to differ in the manner in which they attack tumor tissue by testing them for destructive activity against the respective tumors at intervals of 10 passages. Although it was not possible to influence the neurotropism of the virus, the following changes took place: By continuous passage in sarcoma 180, the oncolytic ability of the virus for this tumor increased; by continuous passage in brain, the oncolytic ability of the virus was greatly decreased; by continuous passage in a non-susceptible tumor (Wagnar osteogenic sarcoma), the virus was changed so that it would destroy it.