AbstractThe erythropoietic stem cell compartment was studied in Friend‐virus (polycythemic strain, FV‐P) infected DBA/2 and NMRI mice with the CFUEand BFUEtechnique. Early after infection there was a depression in CFUEnumber in bone marrow and spleen, followed by an increase of the CFUEconcentration, earlier and more pronounced in the spleen than in the marrow. Three days after FV‐P infection an erythropoietin (Ep) independent CFUEpopulation started to grow and replaced the normal Ep‐dependent population within 8 to 12 days. The shift to Ep independency was not gradual. CFUEcolonies of FV‐P infected bone marrow cells were two to three times larger than control colonies after three days in vitro incubation.BFUEcolonies increased in number during the first days of infection, but were totally lost after more than ten days. After velocity sedimentation of bone marrow cells of FV‐P infected animals, however, the BFUEcontaining fractions showed normal BFUEcolony growth and normal Ep sensitivity. In unfractionated bone marrow cell cultures BFUEcolony growth could be observed later than ten days post infection when the cultures were refed with medium. It was therefore concluded that the loss of BFUEcolony growth after FV‐P infection was an in vitro artefact due to inadequate cultu
展开▼
