title: Cellular proliferation in the spleen of DBA/2 mice infected with a myeloproliferative sarcoma virus(MPSV).
abstract: Cellular proliferation kinetics were investigated in the spleens of DBA/2 mice infected with a myeloproliferative sarcoma virus (MPSV) at three distinct phases of spleen growth: the rapid-growth phase, the slow-growth phase and the regression phase. Using injection of tritiated thymidine in vivo and autoradiographic techniques, we showed that most blast cells proliferate rapidly (cell cycle is equal to 10 h) even during the slow-growth phase. Very massive and rapid cell loss was found during the rapid-growth phase (cell loss factor phi = 80%). By comparing the decrease in specific splenic activity after in vivo injection of 125IUdR and 3HTdR, we were able to show a large reutilization of tritiated thymidine (R = 57%), visible less than 7 h after injection of isotopic DNA precursors. Thus, MPSV-infected spleen cells were shown, for the most part, to be short-lived cells: almost one-half mature into erythrocytes and the others rapidly die in situ.
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D002455:Cell Division; D004273:DNA, Neoplasm / Q000096:biosynthesis; D008297:Male; D051379:Mice; D008811:Mice, Inbred DBA; D009929:Organ Size; D009053:Sarcoma Viruses, Murine / Q000254:growth & development; D012513:Sarcoma, Experimental / Q000209:etiology / Q000473:pathology*; D013154:Spleen / Q000473:pathology; D013160:Splenic Neoplasms / Q000209:etiology / Q000473:pathology*
chemical_list: D004273:DNA, Neoplasm