title: Myeloproliferative Sarcoma Virus stimulates pluripotent hematopoietic stem cells and provokes tumoral transformation of the hematopoietic microenvironment in vitro.
abstract: The Myeloproliferative Sarcoma Virus (MPSV) induces an increase in the number and concentration of pluripotent stem cells in long-term murine bone marrow cultures. This is followed by an increased number of precursor cells of the granulocyte and macrophage lines (GM-CFC). This increase is comparable to that observed in DBA/2 mouse spleens in vivo two to three weeks after viral infection. Proliferation of CFUs and GM-CFC decreases five weeks after infection with MPSV, in parallel to the gradual decline of reverse transcriptase activity in the culture medium. GM-CFC which can proliferate in the absence of added colony stimulating factor (CSF) were detected at week 6 post MPSV infection. Adherent tumor cells were observed nine weeks after infection. These fibroblast type cells gave rise to a permanent line which produced a CSF-like activity. Our results show that MPSV causes the tumoral transformation of fibroblast-like cells of the bone-marrow hematopoietic microenvironment. In addition, MPSV also strongly stimulates the proliferation of hematopoietic stem cells. MPSV is, until now, the first murine retrovirus which exhibits such properties.
mesh_terms: D000818:Animals; D002471:Cell Transformation, Neoplastic / Q000473:pathology*; D002472:Cell Transformation, Viral; D002478:Cells, Cultured; D003114:Colony-Forming Units Assay; D003115:Colony-Stimulating Factors / Q000032:analysis; D006412:Hematopoietic Stem Cells / Q000382:microbiology / Q000473:pathology; D051379:Mice; D008811:Mice, Inbred DBA; D009196:Myeloproliferative Disorders / Q000382:microbiology*; D009053:Sarcoma Viruses, Murine
chemical_list: D003115:Colony-Stimulating Factors