Radiobiological features of fresh leukemic bone marrow progenitor cells in XXXX .

@entity15002 @entity1 @entity981
The radiobiological features of leukemic progenitor cells ( @entity15002 ) freshly obtained from 14 T-lineage @entity981 ( @entity981 ) and 11 B-lineage @entity981 @entity1 were evaluated using @entity15002 colony assays. No significant radiobiological differences were observed between T-lineage versus B-lineage @entity981 @entity15002 . Notably, the D0 values displayed a significant interpatient variation in both groups, indicating a pronounced heterogeneity in the radiation sensitivity of @entity15002 . @entity15002 from some @entity1 were very radioresistant, and in additional experiments using cryopreserved bone marrow blasts, up to 32% of @entity15002 could survive 1600 cGy delivered at 100 cGy/min. In six of 11 T-lineage @entity981 cases and five of ten B-lineage @entity981 cases, a distinct initial shoulder was present on the single dose radiation survival curves, providing circumstantial evidence that @entity15002 are able to repair sublethal radiation damage. A greater proportion of @entity15002 survived 400 cGy when the dose was delivered in two fractions instead of a single dose, providing direct evidence that @entity15002 in @entity981 possess a substantial capacity to repair sublethal radiation damage. The interpatient differences in Dq and recovery factor values indicated a marked heterogeneity in the ability of @entity15002 to repair sublethal radiation damage. Analysis of the dose rate effects on the radiation survival of @entity15002 in four @entity981 cases suggested that the radiation sensitivity of @entity15002 is dose rate dependent. Normal bone marrow progenitor cells (colony-forming unit, granulocyte-macrophage, and burst-forming unit, erythroid) were more radiosensitive and unable to repair sublethal radiation damage. To our knowledge, this report represents (a) the first detailed comparative analysis of the radiobiological features of freshly obtained @entity15002 in T-lineage and B-lineage @entity981 @entity1 , and (b) the first elucidation of radiobiological differences between leukemic @entity981 versus normal bone marrow progenitor cells.
