Table 1

NBT maturation assays performed on NB4-S1 APL cells after 5 days of treatment with RA (1 μM) [designated +RA] or vehicle (DMSO) [designated −RA] or transduction of the UBE1L retrovirus, [designated +UBE1L] as compared to transduction of the same retrovirus without an insert [designated −UBE1L]

Cell lineNBT, %
NB4-S1 (−RA)0
NB4-S1 (+RA)92
NB4-S1 (−UBE1L)0
NB4-S1 (+UBE1L)0
  • NBT-positive NB4-S1 cells appeared after RA treatment, but transduction of UBE1L or a control vector did not induce morphological maturation (data not shown) or a positive NBT assay. For each assay, 200 cells were scored and percentages of NBT-positive cells are shown.