Growth of murine sarcoma and murine xenotropic leukemia viruses in Japanese quail: induction of tumors and development of continuous tumor cell lines.

The BALB/c murine endogenous xenotropic leukemia virus pseudotype of m1 Moloney sarcoma virus [m1MSV(B-MuX)] was used to productively transform diploid Japanese quail embryo cells. The majority of newly hatched quail inoculated with m1MSV(B-MuX)-transformed quail embryo fibroblast cells rapidly developed tumors which were predominantly locally invasive fibrosarcomas, but metastases were observed in two birds. In two tumor-bearing quail, lymphosarcomas were observed in conjunction with fibrosarcomas. Quail inoculated with m1MSV(B-MuX) virus or quail embryo fibroblast cells infected with helper leukemia virus did not develop tumors. A cell culture derived from one quail tumor was shown to be oncogenic in newly hatched quail. Viruses produced by m1MSV(B-MuX)-infected quail cells or quail tumors had envelope properties of BALB-derived murine xenotropic leukemia virus as measured by host range, interference, and neutralization. Virus structural antigens, proteins with molecular weights of 30,000 and 70,000, were detected in tumors and tumor-derived cell lines by immunofluorescence and gel diffusion. Sera from tumored quail had high titers of type-specific BALB-derived murine xenotropic leukemia virus antibodies as determined by neutralization and immunoprecipitation. Antibodies to the putative m1 Moloney sarcoma virus mos gene product were not detected in sera from tumored or regressor quail.