Repopulation by adoptively transferred BMCs in lethally irradiated recipients. BMCs were harvested from legs of long-term chimeras (prepared with [;n = 5] or without [♦;n = 7] MI) or from sternum and vertebrae of chimeras prepared with MI (▴; n = 5) 40 weeks after BMT. BMCs (1 × 10⁷) were injected to lethally irradiated (10 Gy) CD45.1 mice. Mean percentages of donor CD4 cells, CD8 cells, B cells, monocytes, and granulocytes in WBCs are shown at the indicated time points. Statistically significant differences were seen in chimerism levels in every lineage between recipients of marrow from the no irradiation group versus the 7-Gy MI group (except CD4 cell lineage at 2 weeks). Error bars indicate SD.