title: Genesis of a new spleen focus-forming virus: possible role of MCF viruses.
abstract: A Friend mink cell focus-inducing (Fr-MCF) virus isolated from a Friend tumor cell line was able to induce acute erythroleukemia associated with polycythemia when injected as a Friend murine ecotropic leukemia virus (F-MuLV) pseudotype into adult Swiss and ICFW mice. One virus isolate recovered from leukemic cells and designated as FV-F3 presented the following properties: (i) persistence of the same leukemogenic power when propagated in vivo and in vitro; (ii) in vivo spleen focus-forming (SFFV) capacity; (iii) presence of erythropoietin (EPO)-independent CFU-E in leukemic animals; (iv) expression of a 32 RNA specifically recognized by a SFFV probe, in FV-F3 infected cells; and (v) expression in FV-F3-infected cell of polypeptides in the range of gp52 SFFV. Peptide analysis of these products revealed close similarities with the parental MCF virus. These data suggest that a SFFV genome arose by genetic recombinational events involving MCF virus.
mesh_terms: D000818:Animals; D002460:Cell Line; D004921:Erythropoietin / Q000494:pharmacology; D009052:Leukemia Virus, Murine / Q000235:genetics / Q000502:physiology*; D004915:Leukemia, Erythroblastic, Acute / Q000382:microbiology*; D007942:Leukemia, Experimental / Q000382:microbiology*; D051379:Mice; D011086:Polycythemia / Q000382:microbiology*; D012367:RNA, Viral / Q000032:analysis; D011995:Recombination, Genetic; D013154:Spleen / Q000382:microbiology; D014759:Viral Envelope Proteins; D014764:Viral Proteins / Q000096:biosynthesis
chemical_list: D012367:RNA, Viral; D014759:Viral Envelope Proteins; D014764:Viral Proteins; D004921:Erythropoietin