title: Azathioprine-induced lymphocytic neoplasms of NZB mice lack ecotropic murine leukaemia virus.
abstract: NZB mice injected intramuscularly throughout a 6-month period with the immunosuppressant azathioprine (Imuran) developed lymphocytic lymphomas 6--7 months after treatment was initiated. These malignancies were quite distinct from the reticulum-cell neoplasia which occurs spontaneously in the strain, and were readily transplantable to NZB or histocompatible BALB/c recipients. Xenotropic, but not ecotropic murine leukaemia virus (MuLV) was detected in leukaemic tissues of some donor and recipient NZBs when tested in vitro by co-cultivation with permissive cell lines, genome rescue, XC and viral polymerase assays. Virus filtrates prepared from donor leukaemic tissues were non-pathogenic when injected into newborn C3H mice. These results are evidence against a mandatory ecotropic MuLV genome in lymphocytic neoplasia.
mesh_terms: D000818:Animals; D001379:Azathioprine; D002460:Cell Line; D009052:Leukemia Virus, Murine / Q000302:isolation & purification*; D007942:Leukemia, Experimental / Q000382:microbiology; D008228:Lymphoma, Non-Hodgkin / Q000139:chemically induced* / Q000382:microbiology; D051379:Mice; D008807:Mice, Inbred BALB C; D008809:Mice, Inbred C3H; D008814:Mice, Inbred NZB; D009368:Neoplasm Transplantation; D009374:Neoplasms, Experimental / Q000139:chemically induced / Q000382:microbiology; D014185:Transplantation, Isogeneic
chemical_list: D001379:Azathioprine