Fig. 6.

Absence of PD-L1 signaling impairs tolerance induction mediated by the infusions of ECDI-treated donor cells. (A) Islet graft survival in PD-L1^−/− recipients with or without ECDI treatment. Day 0 indicates the day of islet transplantation. (B) Anti-donor IFN-γ production by PD-L1^−/− vs. wild-type recipients receiving ECDI treatment. *, PD-L1^−/− ECDI-treated vs. wild-type ECDI-treated; P = 0.0005. (C) Quantification of the CD4⁺CD25⁺Foxp3⁺ T-cell population in peripheral lymphoid organs from PD-L1^−/− vs. wild-type recipients receiving ECDI-treated cells.