Figure 1.

The mineralized component of an autograft is the major contributor to bone regeneration. (A) H&E staining of a representative tissue section through the mineralized (top) and marrow (bottom) components of a bone graft. The dotted line demarcates the mineralized matrix (mm). Representative tissue sections through the mineralized component, transplanted to the sub-renal capsule (SRC) and harvested after 5 days then stained (B) for DAPI to detect viable cell nuclei, (C) TRAP to detect osteoclast activity, (D) Ki67 to detect proliferating cells, and (E) Runx2 and (F) Osterix to detect osteoprogenitor cells. (G) Quantification of Runx2 and Osterix expression in the mineralized matrix and marrow components. The osteogenic capacities of the marrow vs. the mineralized component were assessed by transplantation to the SRC. Representative tissue sections immunostained to detect (H) Runx2 and (I) Osterix expression, and stained to detect (J) ALP activity. (K) Aniline blue histology identified new bone matrix. Representative tissue sections through demineralized bone matrix (DBM) combined with the marrow component, transplanted to the SRC. After 7 days, tissues were harvested then stained for (L) Aniline blue, (M) DAPI, (N) GFP expression, and (O) ALP activity. In all panels the dotted yellow line indicates the boundary between the host kidney and the transplanted material. Abbreviations: as noted in text. Scale bars = 50 µm. Asterisk indicates p-value < 0.05.