The neutrophil defect in Mll5^−/− mice is cell-autonomous. (A) Cytospin preparations of bone marrow cells stained with Wright Giemsa stain from Mll5^−/− recipients that were transplanted with bone marrow cells from Mll5^+/+ (left, original magnification ×200, inset digitally enlarged) or Mll5^−/− (right, original magnification ×200, inset ×400) mice, harvested 6 months after transplantation. Quantification of the oxidative burst activity of neutrophils in peripheral blood of Mll5^−/− mice transplanted with Mll5^+/+ (n = 4) or Mll5^−/− (n = 2) bone marrow, 8 weeks after transplantation. Graphs showing (B) percent of neutrophils producing reactive oxidants and (C) enzymatic activity of reactive oxidants per cell. (D) Mean and SD of reconstituted hematopoietic cells in peripheral blood of Mll5^−/− recipients transplanted with Mll5^+/+ (n = 4, □) or Mll5^−/− (n = 2, ) bone marrow cells, automated cell counts 8 weeks after transplantation. (E) Mean and SD of reconstituted hematopoietic cells in bone marrow of Mll5^−/− recipients transplanted with Mll5^+/+ (n = 4, □) or Mll5^−/− (n = 2, ) bone marrow cells, immunophenotyping by flow cytometry 4 weeks after transplantation. (F) Granulocyte progenitors in bone marrow of Mll5^−/− recipients transplanted with Mll5^+/+ (n = 8) or Mll5^−/− (n = 6) bone marrow cells; mean number and SD of 10-day G-CSF–responsive colony-forming cells formed per 10⁵ bone marrow cells 1 and 6 months after transplantation. (G) Cytospin preparations of bone marrow cells stained with Wright Giemsa stain from Mll5^+/+ recipients that were transplanted with bone marrow cells from Mll5^−/− mice (original magnification ×200, inset ×400), harvested 6 months after transplantation.