PROPAGATION AND CHARACTERIZATION OF A C-TYPE VIRUS FROM A RHABDOMYOSARCOMA OF A CORN SNAKE

The presence of a C-type virus in tissues of an embryonic rhabdomyosarcoma of a corn snake Elaphe guttata was previously described, based upon electron microscopic observations. A virus, corn snake retrovirus (CSRV) has been recovered from the tumour tissue by inoculation of a tissue homogenate on to either the rattlesnake fibroma cell line or early passage cells derived from rattlesnake heart or kidney. The virus was classified as a retrovirus on the basis of electron microscopic observations of fine structure and morphogenesis, and the demonstration of virion-associated reverse transcriptase and a buoyant density of 1.16. Polypeptide analysis of CSRV performed by polyacrylamide gel electrophoresis revealed the presence of five major polypeptides: three had mobility analogous to that of structural polypeptides of viper retrovirus (VRV) but two polypeptides, one of mol. wt. approx. 16000 and a glycoprotein of mol. wt. approx. 72000, were unique. Antigenic comparison of CSRV and VRV by agar gel immunodiffusion revealed that CSRV possesses a major antigenic determinant which is different to that of VRV. CSRV propagated in rattlesnake fibroma cells was demonstrated to be slowly cytopathic for rattlesnake heart and kidney cells in vitro.