| Objective: Established the model of abdominal cardiac transplantation in rats from SD to Wistar rats,and infused alloantigen-pulsed host immature dendritic cells(imDC) to receptor via peripheral intravenous, to observe whether effective amplification receptor antigen-specific CD4+CD25+ regulatory T cells (Treg), and explored influence of alloantigen-pulsed host imDC in allograft immune rejection reaction and reveal its mechanism.Methods: Low-dose GM-CSF in vitro culture host bone marrow-derived dendritic cells (DC), added the donor soluble antigen in the culturing process, and infused to receptor via peripheral intravenous.Donor(SD rats) and receptor(Wistar rats) of 24 were randomly divided into four groups, Group A(control group): The heart from SD rat was transplanted into the abdomen of Wistar rat and receptor without any treatment. Group B(CsA group): receptor was injected CsA 10mg/kg/d via intraperitoneal after heart transplant in 0～9d. Group C(imDC group): receptor was injected alloantigen-pulsed host imDC 2×106 via the tail vein before preoperative 7th day. Group D(imDC+CsA group): receptor was injected alloantigen-pulsed host imDC 2×106 via the tail vein before preoperative 7th day, the else as the Group B. Observing target: cardiac allograft survival time, pathological changes, receptor CD4+CD25+Treg cell change, T cell proliferation inhibition test, and serum TGF-β1, IL-10 change.Results: (1)Heart mean survival time (MST): Group A: 6.8±0.83d, Group B: 16.2±1.30d, Group C: 18±2.91d, Group D: 49.2±8.01d. The MST of Group D was significantly prolonged than GroupA,B,C, P<0.05. (2) the results of receptor CD4+CD25+Treg in peripheral blood: Group A: 2.66±0.47%, Group B: 2.7±0.43%, Group C: 7.84±0.51%, Group D: 8.4±0.60%. The peripheral blood CD4+CD25+Treg of Group C,D was significantly higher compared with Group A,B, P<0.05. It had no significant difference between Group C and Group D, P>0.05. (3) T-cell proliferation inhibition test:The experimental group inhibition rate: 79.22%, third-party stimulation inhibition rate:12.77%. alloantigen-pulsed host imDC induced CD4+CD25+Treg has antigen-specific. (4) the results of receptor TGF-β1 in peripheral blood: Group A: 211.07±5.97 pg/mL; Group B: 210.19±8.08pg/mL; Group C: 469.40±10.55pg/mL; Group D: 477.52±6.51 pg/mL. the TGF-β1 levels of GroupC,D was significantly higher compared with GroupA,B, P<0.05. It had no significant difference between Group C and Group D, P>0.05. (5) the results of receptor IL-10 in peripheral blood: Group A: 21.30±1.63pg/mL; Group B: 21.20±1.71pg/mL; Group C: 50.79±1.59 pg/mL; Group D: 51.09±1.96 pg/mL. the TGF-β1 levels of GroupC,D was significantly higher compared with GroupA,B, P<0.05. It had no significant difference between Group C and Group D, P>0.05.Conclusion: 1,Infusion alloantigen-pulsed host imDC via peripheral intravenous can induced receptor antigen-specific CD4+CD25+Treg increased. 2,Preoperative infusion alloantigen-pulsed host imDC via peripheral intravenous, combined with postoperative short-term using immunosuppressive agents could effectively inhibit postoperative acute and chronic rejection, and significantly prolonged allogeneic heart graft survival time. 3,Cytokines were involved in CD4+CD25+Treg cells inducing immune tolerance process. |
