Ultrastructure of Gliomas Induced in Hamsters With Rous Sarcoma Virus

Abstract

The ultrastructure of gliomas induced in hamsters with intracerebral inoculation of Rous sarcoma virus (RSV) has been studied. The strains of RSV used in the present investigation were Bryan high-titer and Schmidt-Ruppin. A high degree of pleomorphism was recognized among the neoplastic cells. Nevertheless, the ultrastructural characteristics of most cells were consistent with those reported for neoplastic astrocytes in man and resembled normal protoplasmic and fibrillar astrocytes or had the characteristics of gemistocytic astrocytes. Mitosis of the glial cells and proliferation of the vascular stroma were particularly prominent, these characteristics being consistent with the diagnosis of malignant astrocytoma. “Nuclear bodies” and crystalline aggregates of unknown material were observed within the nuclei of the neoplastic cells. No virus particles with the morphology of the causative agent were found. The significance of the failure to find such particles in the hamster gliomas, though they were found in dog meningiomas induced with RSV, is discussed.