Repopulation units in injected and noninjected femur of nonablated mice.
After injection of 5 × 105 Lin− Ly5.1 cells into one of the femur cavities of F1 nonablated mice, 1.5 × 106 marrow cells were collected from each of the injected and noninjected femurs at different times. The collected cells, which contained Ly5.1 and F1 cells, then were infused into lethally irradiated Ly5.2 mice for the competitive repopulation assay. Lin− donor cells prior to femur injection were mixed with F1 BM (2% donor cells) for the competitive repopulation assay. Peripheral blood was collected from Ly5.2 recipients 6 months later for FACS analysis to determine the percentages of repopulation from Ly5.1 and F1 cells. Repopulation units per 100 000 donor cells were calculated based on the method described by Jordan et al.12
