Engraftment of bone lining cells after transplantation with TBM from 3.6-blue donor mice. (A-B) An image of frozen decalcified bone (A, femur; B, tibia) from a 3.6-green recipient rescued with systemic TBM from a 3.6-blue donor. The 3.6-blue cells (arrows) are present on the bone surface admixed with 3.6-green cells. Note that the 3.6-blue cells do not extend into the osteocyte layer. (C-D) An image of the bone from a 2.3-green host that received an intramedullary injection of TBM from a 3.6-blue mouse. The 3.6-blue cells line the bone surface whereas the host cells express 2.3-green on the bone surface and within osteocytes. (C) Injected tibia. (D) The contralateral femur also demonstrates 3.6-blue cells, indicating engraftment by a systemic route. (A-D) Original magnification, × 200.