FIG. 2.

Total body irradiation (TBI) significantly increases two-dimensional (2D) bone volume following BMSC transplantation in a cell dose-dependent fashion. The standard 2D bone histomorphometric parameter BV/TV was assessed in the proximal tibiae 4 weeks post-transplantation. (A) Overview of a representative hematoxylin and eosin (H&E)-stained central cross-section (EP: epiphyseal plate, M: marrow, T: trabecular bone, C: cortical bone, 2.5×, scale bar 500 μm). The 876.9×657.1 μm rectangular ROI (20×, scale bar 20 μm, 1388×1040 pixels per image, 576211.68 μm² or 0.58 mm² combined total area in four identical quadrants) is outlined in dashed lines. (B) One H&E-stained central cross-section 20× ROI quadrant. (C) The same 20× ROI depicting bone tissue in black (Photoshop wand tool, tolerance: 10). (D) Final black-and-white image mask of the 20× ROI showing bone tissue in black and all other tissue in white. Using ImageJ, the entire image area was calculated as tissue area (T.Ar) and the black-colored area was summarized as bone area (B.Ar; default ImageJ wand tool) to calculate BV/TV. Per definition, BV/TV is numerically identical with the corresponding area/area ratio B.Ar/T.Ar. (E) Nonirradiated and (F) irradiated animals (*p<0.05, **p<0.01 BMSC-transplanted vs. vehicle controls; ^ap<0.05, ^bp<0.01 1.32×10⁵ cells/mL vs. higher doses; ^$p<0.01 1.32×10⁶ cells/mL vs. higher doses, n=3 per group). Color images available online at www.liebertpub.com/tea