Objective      To study the inhibitory effects of different sources of dendritic cells (DCs) on immunological rejection after allogeneic tooth transplantation in rats.       Methods      The donor and recipient tooth transplantation models were isolated from respectively 60 BN rats and 80 Lewis rats

and the rats were divided randomly. Group A was a syngen

eic transplantation group

in which Lewis teeth were transplanted to Lewis rats

while group B

group C and group D were allogeneic transplantation groups

in which BN teeth were transplanted to Lewis rats. The recipients in group A and B were injected with PBS via the tail vein at the 7th day before the operation

and the recipients in group C and group D were injected with 1×10

6

donor and recipient tolerogenic DCs at the 7th day before the operation

respectively. Five rats that were randomly selected from each group were sacrificed at 1

2

4 and 8 weeks after operation

and the pathological examinations of the transplanted teeth were performed. The concentrations of IL-2

IFN-γ

IL-4 and IL-10 in the peripheral blood were detected using ELISA.       Results      At each time point

the levels of IL-2 and IFN-γ in group C and group D were higher than those in group A

but were lower than those in group B. Additionally

the levels of IL-4 and IL-10 were higher in group C and group D than in group A and group B (P0.05). Compared with group D

the level of IL-2 in group C was lower at 1 week but higher at 8 weeks (P0.05)

and the levels of IL-4 and IL-10 were higher at 1 and 2 weeks but lower at 8 weeks (P0.05). The root resorption in group C and group D was less than that in group B but was more than that in group A (P0.05). Compared with group C

root resorption in group D was similar at 2 and 4 weeks but less at 8 weeks (P0.05). The degree of inflammatory cell infiltration in group C and group D was lower than that in group B but was higher than that in group A (P0.05).       Conclusion      Donor and recipient tolerogenic DCs may inhibit immunological rejection after allogeneic tooth transplantation in rats. Donor tolerogenic DCs have greater inhibitory effect on early acute immunological rejection

while recipient tolerogenic DCs showed greater inhibitory effect on later chronic immunological rejection.