Effects of Rauscher murine leukemia virus on hemopoietic organ-derived clonogenic fibroblasts.
Fibroblast colony-forming units (CFU-F) in bone marrow and spleen were investigated after infection of BALB/c mice with the Rauscher leukemia virus complex (RLV) or with cellularly cloned helper virus (R-MuLV). Both viral preparations induced a transient suppression of CFU-F prior to the development of leukemia. A second CFU-F decrease was observed in the terminal phase of R-MuLV-induced chronic lymphoid or myeloid leukemias, but not in mice with a RLV-induced acute erythroleukemia, which are highly viremic. When a number of Rauscher virus transformed leukemic cell lines were injected intravenously an erythroid and a T-cell line suppressed CFU-F values, but a third non-virus producing B-cell line did not. In contrast to the in-vitro situation, in-vitro inhibition of CFU-F was only observed in conditioned medium of an erythroid cell line with undetectable reverse transcriptase activity, whereas conditioned medium of lymphoid and myeloid cell lines were not inhibitory irrespective of reverse transcriptase activity. Together these results indicate that murine leukemia viruses can suppress the numbers of detectable CFU-F in vivo in an early phase of the disease and that leukemic cells may inhibit CFU-F proliferation by a mechanism which is not related to viremic state of the animal or the production of virus by these cells.
Brockbank
K G
KG
de Both
N J
NJ
Voerman
J S
JS
van der Haven
M
M
D000818:Animals; D002460:Cell Line; D003115:Colony-Stimulating Factors / Q000096:biosynthesis; D003470:Culture Media; D005347:Fibroblasts / Q000473:pathology; D006412:Hematopoietic Stem Cells / Q000473:pathology*; D004915:Leukemia, Erythroblastic, Acute / Q000473:pathology; D007942:Leukemia, Experimental / Q000473:pathology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008811:Mice, Inbred DBA; D009368:Neoplasm Transplantation; D012194:RNA-Directed DNA Polymerase / Q000032:analysis; D011925:Rauscher Virus
D003115:Colony-Stimulating Factors; D003470:Culture Media; D012194:RNA-Directed DNA Polymerase