Engraftment and multilineage differentiation of clonal mesenchymal stem cells (CMG cells). (A) The experimental protocol for the intra-BM transplantation of CMG cells transfected with MSCV-EGFP is shown. (B-G) Transplanted CMG cells were observed in the recipients' BM. CMG cells were recognized as brown cells by immunohistochemistry. (B) CMG cells differentiated into adipocytes (arrows) (magnification, × 100). The rectangle in panel B is shown at a higher magnification (× 200) in panel C. (D) CMG cells also differentiated into osteocytes (arrows). Undifferentiated CMG cells exhibiting spindlelike shapes were also observed (arrowheads) (magnification, × 100). The rectangles in panel D are shown at higher magnifications in panels E (× 200) and F (× 400). (G) Undifferentiated CMG cells in other part (× 200). (H, I) CMG cells also were found in the liver (H) and kidney (I) by immunofluorescence photography. Bars indicate 10 μm. The green and blue signals indicate EGFP and nuclei, respectively.