Prolongation of cardiac allograft survival by systemic administration of immature recipient dendritic cells deficient in NF-κB activity

Objective: To develop a more applicable approach that uses recipient-derived dendritic cells (DC) for organ transplantation. Summary Background Data: Systemic administration of immature donor DC that are deficient in costimulatory molecules delays the onset of allograft rejection. However, this approach requires in vitro DC propagation and would not be applicable to deceased donor organ transplantation. Methods: DC were propagated from C3H (H2^k) mouse bone marrow with GM-CSF; their maturation was arrested by treatment with oligodeoxyribonucleotides (ODN) specifically against nuclear factor (NF)-κB. The DC were pulsed with B10 (H2^b) splenocyte lysate. DC phenotype was examined by flow cytometry. Their allostimulatory activity was assessed in vitro by MLR and CTL assays and in vivo by the influence on B10 cardiac allograft survival. Cytokine profiles were analyzed by ELISA and RNase protection assay. NF-κB activity in DC nuclear protein was detected by gel shifting assay. Results: Compared with mature DC, NF-κB ODN-treated immature DC pulsed with B10 (H2^b) spleen cell lysate elicited markedly lower proliferative responses and correlated with reduced IFN-γ and increased IL-10 production. In contrast to administration of mature C3H DC pulsed with B10 antigen that accelerated rejection of B10 cardiac allografts, a single injection of NF-κB ODN DC pulsed with donor antigens significantly prolonged allograft survival in an antigen-specific manner. This was associated with induction of T-cell hyporesponsiveness and enhanced T-cell apoptosis. Conclusions: An approach to use recipient DC as a "vaccine" strategy provides a more feasible approach for deceased-donor organ transplantation.