title: Several classes of retroviruses are produced by an AKR mouse T lymphoma cell line.
abstract: Characterization of the viruses produced by the spontaneous T lymphoma cell line SL3 is presented. Using supernatant fluids or direct co-cultivation of cells, the SL3 cell line was found to produce replication-defective viruses in excess of replication-competent viruses. The replication-competent viruses released were predominantly those negative in the XC plaque assay (XC-); XC+ viruses represented a minor population. However, when the SL3-derived viruses were passed in mouse embryo fibroblasts, XC- viruses were rarely recovered, and XC+ viruses were readily isolated. These viruses were all ecotropic and lymphomagenic. Viruses with dual host range and non-oncogenic ecotropic viruses were not isolated from the lymphoma cells. Two replication-defective viruses from SL3 cells were studied. Both could be rescued by non-oncogenic retroviruses and were then lymphomagenic. One defective virus appeared related to XC+ viruses. In these studies, the XC+ and XC- viruses appeared to represent two different interference classes using separate cell receptors. Taken together, these experiments show that the SL3 T lymphoma cells replicate a variety of viruses most of which are lymphomagenic. Virus replication and/or virus integration may be the means of maintaining the malignant phenotype of these T lymphoma cells.
mesh_terms: D000818:Animals; D004261:DNA Replication; D003673:Defective Viruses / Q000302:isolation & purification; D015683:Gene Products, gag; D005814:Genes, Viral; D008223:Lymphoma / Q000382:microbiology*; D051379:Mice; D008806:Mice, Inbred AKR; D012190:Retroviridae / Q000235:genetics / Q000302:isolation & purification*; D013601:T-Lymphocytes / Q000382:microbiology; D013953:Thymus Neoplasms / Q000382:microbiology*; D014764:Viral Proteins / Q000032:analysis; D014779:Virus Replication
chemical_list: D015683:Gene Products, gag; D014764:Viral Proteins