Transplantation of bone marrow fibroblastoid stromal cells in mice via the intravenous route

Kinetics of fibroblastic colony-forming cells (CFU-F) were studied in mouse bone marrow after lethal total body irradiation and intravenous bone marrow transplantation. After an initial decrease, CFU-F numbers recovered, and plateaued 5 weeks post-treatment at 10% of normal values. Using chromosome-marked donor bone marrow cells we found that 1 day after transplantation 72% of donor CFU-F had reached the recipient's bone marrow, indicating a highly specific lodgment of CFU-F. Three months after transplantation donor CFU-F were still detectable and comprised about half of the femoral CFU-F population. It is concluded that CFU-F, a component of the haemopoietic microenvironment, are transplantable via the intravenous route.