树突状细胞对大鼠牙移植后组织学及Th1/Th2细胞因子影响的研究

Effect of dendritic cells on histology and Th1/Th2 cytokines after tooth transplan-tation in rats

目的研究不同来源树突状细胞(dendritic cell,DC)对大鼠同种异体牙移植后免疫排斥反应的抑制效果。方法用BN大鼠60只、Lewis大鼠80只分别作为供、受体建立牙移植模型,将动物完全随机分为4组,每组各20只:A组为同基因牙移植组,将Lewis大鼠牙移植到Lewis大鼠;B、C、D组为同种异体牙移植组,将BN大鼠牙移植到Lewis大鼠;A、B组于术前7 d通过尾静脉输注PBS 0.5 ml于受体大鼠体内,C组于术前7 d通过尾静脉输注1×106/只的供体致耐受DC于受体大鼠体内,D组于术前7 d通过尾静脉输注1×106/只的受体致耐受DC于受体大鼠体内。各组于术后第1、2、4、8周随机处死5只大鼠,行移植牙病理学检查和ELISA检测外周血清IL-2、IFN-γ、IL-4、IL-10浓度。结果 C、D组IL-2、IFN-γ在各时间点均高于A组低于B组,IL-4、IL-10在各时间点均高于A、B组(P<0.05)。C组IL-2在第1周时低于D组,到第8周时则高于D组(P<0.05)。C组IL-4、IL-10在第1、2周时高于D组,到第8周时则低于D组(P<0.05)。C、D组牙根吸收较B组有所减少但仍高于A组(P<0.05),C、D组牙根吸收在2、4周时没有差异,在8周时D组低于C组(P<0.05)。C、D组炎性细胞浸润较B组均明显减轻但重于A组。结论供、受体致耐受DC均可抑制大鼠同种异体移植牙的排斥反应,减轻排斥反应程度。供体致耐受性DC对早期急性排斥反应抑制更明显,受体致耐受性DC对晚期慢性排斥反应抑制更明显。

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 syngeneic 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 1×106 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.