Figure 5. In vivo expanded T_Regs co-transplanted with hPBMCs are capable of preventing IL-2 accelerated GVHD in NOD-scid IL2rγc^null mice.

(A, B) Kaplan-Meir curve showing the survival of IL-2 conditioned NOD-scid IL2rγc^null mice injected with hPBMCs alone or hPBMCs along with in vivo expanded T_Regs. T_Regs purified from animals 12 days after reconstitution were used for co-transfer along with hPBMCs at 1∶1 (A) or 1∶5 (B) ratio of T_Regs:PBMCs and the animals were observed for GVHD symptoms. (C, D) Kaplan-Meir curve comparing protection from GVHD conferred by in vitro and in vivo expanded T_Regs. IL-2 conditioned NOD-scid IL2rγc^null mice were injected with hPBMCs only or co-transferred with different ratios of in vitro (C) or in vivo (D) expanded T_Regs and hPBMCs. In all experiments, each group consisted of 3 mice.