TN-C is markedly up-regulated in the BM during myeloablation and hematopoietic recovery. BM sections from days 0, 2, and 10 stained for TN-C (red) in the metaphyseal (A-C) and diaphyseal (D-F) regions of the femoral bone. The bone surfaces are outlined by white dotted lines (A-F). The asterisks in panels C and F show the up-regulation of TN-C beyond the endosteal areas in both the metaphyseal and diaphyseal regions. (G-H) Enlargement of the dotted squares in panels D and F. Arrows indicate the bone surface; arrowheads indicate stromal TN-C expression. (I) High magnification of day 10 BM samples stained for TN-C (red), c-Kit (green), laminin (blue), and DAPI (gray). c-Kit⁺ cells adhered to TN-C expressed perivascularly (costained with laminin; open arrowheads) or away from the vasculature (arrowheads). (J) Western blotting for TN-C in total BM proteins showed that TN-C proteins were detected in 2 bands at 280 and 220 kDa. (K) Quantification of Western blot expression. The mean fluorescence ratio was calculated by dividing the mean fluorescence of the TN-C band by that of the corresponding β-actin band. *P < .05. Scale bars indicate 200 μm in panels A through F; 40 μm in panels G and H; and 10 μm in panel I.