Abstract:Objective
To investigate whether host derived immunedeficient dendritic cells (DC) were capable of inducing immunological tolerance to islet xenografts and to ascertain its mechanism.
MethodsImmunedeficient DC were obtained from marrow of BALB/C mice by inductive differentiation,and loaded with MHC antigen of Wistar rat. The loaded DC were injected into diabetic model mice through tail vein,and,7 days later, islet of Wistar or SD rats were implanted beneath the renal capsule. Survival time of grafts was monitored. Mixed lymphocyte culture and TH1/TH2 cytokine expression were observed.
Results Compared to the untreated mice, the survival time of Wistar islets was significantly prolonged in the pretreated mice(P<0.05), but the survival time of SD islets was not significantly prolonged. T lymphocytes of immunedeficient DC pretreated mice showed mild proliferative reaction, and the expression of TH1/TH2 cytokine was significantly lower.
Conclusions Immunedeficient DC pretreated with donor MHC antigen can induce antigenspecific nonfunction of T cells and low expression of TH1/TH2 cytokines, and thus can effectively prolong the survival time of islet xenografts.