The Effect Of Different Sources Of Tolerance Dendritic Cells On Immune Low Reaction After Allogeneic Tooth Transplantation In Rats

Allogeneic tooth transplantation is an effective methods to repair missing tooth and helps recover masticatory function. Immunological rejection and root resorption after transplantation is still the key that hinder to the success of tooth transplantation. Dendritic cells as a cell therapy, was a new method to induce transplantation tolerance, is concerned in recent years, which can reducing immune rejection or promoting immune tolerance.Objective:In this study, we aimed to use tolerogenic DCs to reduce immunological rejection, induce immune tolerance, and lengthen the functioning time after allogeneic tooth transplantation, which may be applied clinically.Method:Methods: The donor and recipient tolerogenic DCs were isolated from respectively BN rats (SPF level, 6 ~ 8 w, 120-160g, male) and Lewis rats (SPF level, 6 ~ 8 w, 150-200g, male). The donor and recipient teeth transplantation models were isolated from respectively BN rats( clean level, 10-12 w, 180-230 g, male) and Lewis rats(clean level. Lewis, 10-12 w, 260-320g, male). The rats were divided into 4 groups: group A was a syngeneic transplantation group (Lewis→Lewis), and groups B, C, D were allogeneic transplantation groups (BN→Lewis). Recipients in groups A and B were injected with 0.5 ml PBS via the tail vein 7 days before the operation. Recipients in groups C and D were injected with 1*106 donor or recipient tolerogenic DCs via the tail vein 7 days before the operation. Five randomly selected rats from each group were sacrificed at weeks 1, 2, 4 and 8, and pathological examinations of the transplanted teeth were performed. In addition, the concentrations of the cytokines IL-2, IFN-γ, IL-4 and IL-10 in the peripheral blood were detected using ELISA.Result:1. Changes of serum cytokine showed:For each time point, the levels of IL-2 and IFN-γwere higher in groups C and D than in group A but lower than group B. Additionally, the levels of IL-4 and IL-10 were higher in groups C and D than in groups A and B. Compared with group D, the levels of IL-2 in group C were lower at week 1 but higher at week 8, and the levels of IL-4 and IL-10 were higher at weeks 1 and 2 but lower at week 8.2. Inflammatory cells infiltrating, root resorption and healing indicated: The root resorption in groups C and D was less than in group B but more than in group A. Compared with group C, root resorption in group D was similar at weeks 2 and 4 but less at week 8. The periodontal membrane healed points was better in groups C and D compared with group B but less than in group A. inflammatory absorption points in group B was more than group A, C, D. alternative resorption points in group A was less than group B, C, D.Conclusion:1. Both donor and recipient tolerogenic DCs may downregulate Th1 cytokines, skew T cells toward a Th2 subtype, Induce Th2 type cells reaction, increase Th2/Th1 ratio significantly, inhibite the immunological rejection after allogeneic tooth transplantation in rats significantly, reduce rejection rate.2. Both donor and recipient tolerogenic DCs were infused could reduce infiltration of inflammatory cells after allograft tooth transplantation and root resorption, and promoted eriodontal healing.3. Donor tolerogenic DCs had more significant inhibitory effects on early acute immunological rejection, and recipient tolerogenic DCs showed greater effects on later chronic rejection and reducing long-dated root resorption.