Antigenic Properties of a Nonreleaser Neoplasm Induced in the Mouse by Murine Sarcoma Virus

Summary

Pseudotype virus-specific antigcnicity has been detected in a nonreleaser neoplasm, a hemangiosarcoma induced by MSV(MLV), the pseudotype virus of the murine sarcoma virus bearing the envelope of the Moloney leukemogenic virus; MLV was used as a “helper” virus in the rescue of this pseudotype virus. The neoplasm XM-1 was selected by passage through immunologically deficient syngeneic, BC3HF₁ mice. Data from these experiments support the concept that virus-specific cell surface antigens, as detected by transplantation procedures, do exist on RNA virus-induced neoplastic cells, and that these antigens are distinct from antigens of the virus. Though not decisive, the evidence also favors the assumption of a direct relationship between viral genetic material (in the “defective” state) maintained in these neoplastic cells and the presence of tumor-specific transplantation antigens.