Response of Mice to Reovirus Type 3 in Presence and Absence of Ascites Tumor Cells. ∗

Abstract

Summary

A passaged strain of reovirus type 3 (oncolytic virus of Nelson and Tar-nowski) was established in weaned Swiss mice and maintained for 52 weeks by liver transfer in the absence of ascites tumor cells. The only pathologic response was the presence of peritoneal fluid in trace amounts during the first week. Pathogenicity was not altered by prior injection of Eperythrozoon coccoides.

Active virus was recovered from the liver and brain through the 2nd week after injection. It was present in heart's blood and intestinal washings only during the first week but was detectable in peritoneal washings for at least 18 weeks. The virus was identified by oncolysis in the presence of tumor cells, the response in infant mice, and the cyto-pathic reaction in HeLa cell cultures. Interference with the development of a particular murine hepatitis virus by reovirus 3 was observed in nurslings injected with a mixture of the 2 viruses.

The cooperation of Dr. ManChiang Niu in the processing of electron micrographs and the technical assistance of Selma M. Otchin are gratefully acknowledged.