Donor cell engraftment was determined at 1 and 2 months in lethally irradiated recipients after transplantation of BM-MNCs from control or TBI mice treated with vehicle or MnTE as described above in a competitive repopulating assay. The percentage of donor-derived peripheral blood leukocytes (CD45.2+ cells) (A), T cells (CD45.2+Thy-1.2+ cells) (B), B cells (CD45.2+B220+ cells) (C), and myeloid (CD45.2+CD11b+ and/or Gr-1+ granulocyte-monocyte-macrophage) (D) are presented as mean ± SE (5–6 mice/group). a, p<0.05 vs. control; and b, p<0.05 vs. TBI with vehicle. E & F. Representative analyses of donor cell engraftment by flow cytometry. Upper panel: total donor (CD45.2+) cell engraftment; Lower panel: engraftment of donor-derived T (CD45.2+Thy-1.2+ cells), B (CD45.2+B220+ cells), and M (myeloid, CD45.2+CD11b+ and/or Gr-1+) cells.