Sequential blood chimerism of ACI recipients after transplantation of GFP, WT, or BN (third-party) intestine plus GFP-positive BM under TAC immunosuppression. Similar to results of BN-to-LEW SITx experiments, donor-derived GFP-positive cells gradually decreased with time in recipients that received GFP-positive BM or GFP-positive SITx alone. Transplantation of GFP-positive intestine and GFP-positive BM resulted in stable macrochimerism for 120 days. Stable long-term macrochimerism was also achieved when WT intestine graft and GFP-positive BM were transplanted together. However, cotransplantation of third-party intestine (BN) and GFP-positive BM did not result in a long-lasting macrochimerism. *P < .05 versus BM or SITx alone; n = 4 to 13.