Figure 3. Lymphocyte subset and chimerism induction in the Delayed Protocol. (A) In recipients treated with the conditioning regimen without anti-CD8 mAb, rapid homeostatic recovery of CD8⁺ Tmem was observed after day 5. CD4⁺ T cells were not completely deleted with a nadir around 100/mm³. (B) By adding humanized anti-CD8 mAb to the conditioning regimen, CD8 Tmems were effectively suppressed until day 30. CD4 Tmem levels were even higher after administration of the modified regimen. (C) All recipients who received the delayed protocol at 4 mo without anti-CD8 mAb (4M) failed to develop chimerism. By adding humanized anti-CD8 mAb to the conditioning regimen, recipients consistently developed multilineage chimerism despite the presence of residual CD4 Tmem.