FIGURE 4.

Photomicrographs of H&E stained thin sections of bone marrow sterna showing representative bone marrow cellularity in all groups on day 14. Panels (A) and (B): Bone marrow sterna pretreated with either vehicle or 10 mg/kg RRx-001 on day 14 after sham-irradiation. Panel (C): Vehicle-treated sternal bone marrow 14 days after sublethal irradiation illustrated severe hypocellularity as evident by marrow space demonstrating only residual stromal fat (visualized as increased marrow white space). Panel (D): RRx-001-treated sternal bone marrow 14 days after sublethal irradiation showed significantly increased cellularity as seen by the increased amounts of cells stained purple and decrease in the visualized stromal adipose tissue (white space) (×100 magnification).