转染IKK2dn的受者树突状细胞回输延长同种异体肾移植大鼠的存活时间

目的 探讨IKK2dn基因转染并负载供者抗原的受者未成熟树突状细胞(imDC)延长同种异体肾移植大鼠的存活时间及其机制.方法 获取和培养Lewis大鼠骨髓源性DC,转染IKK2dn并负载BN大鼠可溶性抗原进行体外实验,检测CD86和主要组织相容性复合物(MHC)Ⅱ的表达及DC刺激T淋巴细胞增殖的能力.肾移植受者为Lewis大鼠,用随即数字表法分DC组、空转染组、转染组、对照组,术前7d分别输注1×10~7个D、Adv-0-DC、负载BN抗原的Adv-IKK2dn-DC和等量生理盐水,供者均为BN大鼠.另设第三方供者组,术前处理同转染组,供者为Wistar大鼠.移植后检测各组受者T淋巴细胞的增殖能力及血清白细胞介素2(IL-2)和γ干扰素(IFN-γ)的表达水平,观察各组大鼠的存活时间和发生排斥反应情况.结果 DC的体外实验结果显示:与转染IKK2dn前相比,转染后DC仍能低水平表达CD86和MHC Ⅱ,负载供者抗原后CD86和MHCⅡ表达均增加,而转染IKK2dn后再负载供者抗原,CD86和MHC Ⅱ的表达未发生明显变化;DC负载供者抗原后,刺激T淋巴细胞增殖的能力明显增强(P<0.05),而转染IKK2dn并负载供者抗原后不能有效刺激T淋巴细胞增殖.肾移植术后的检测结果显示:转染组T淋巴细胞的增殖能力明显低于其他4组(P<0.05或P

Prolongation of rat renal allograft survival by recipient-derived immature dendritic cells transfected with IKK2dn gene

Objective To investigate the effect and mechanisms of recipient-derived immature dendritic cells(imDC) transfected with IKK2dn and loaded with donor antigen on renal allografts survival in the rats.Methods DC were cultured from recipient rats'(Lewis) bone marrow,transfected with IKK2dn and loaded with donor antigen.The expression of CD86 and MHC Ⅱ was detected,and the ability of DC stimulating lymphocyte proliferation in vitro was measured.Male Brown Norwav rats and Lewis rats were used as donors and recipients respectively.Four groups were set up(DC group,empty transfection group,transfection group and control group),receiving 1×10~7 DC,Adv-0-DC,Adv-IKK2dn-DC loaded with BN antigen,and equal volume of normal saline,respectivelv 7 davs before transplantation.In the third party donor-group,Wistar rats as donors were treated the same as DC;group before transplantation.After transplantation,the T lymphocyte proliferation in reciPients was measured and the expression of serum IL-2 and IFN-γ was detected.The survival time of recipients and the acute reiection were observed.Pathological changes were examined tO identify the grade of rejection.Results DC assessment in vivo revealed that the transfected DC could still express CD86 and MHC Ⅱ in a low level as compared with those not transfected with IKK2dn. After DC were loaded with donor's antigen,the expression of CD86 and MHC Ⅱ was up-regulated.After DC were transfected with IKK2dn before loaded with donor's antigen, the expression of CD86 and MHC Ⅱ had no significant change. When DC were loaded with donor's antigen, its allostimulatory activity of T lymphocyte proliferation was enhanced (P<0. 05). When DC were transfected with IKK2dn before loaded with donor's antigen, its allostimulatory activity of T lymphocyte proliferation was not enhanced. Compared with control groups, IKK2dn-transfected DC pulsed with BN splenocyte lysate markedly prolonged the survival of renal allografts (26. 8±1.76d, P<0.01), and elicited markedly lower proliferative responses and reduced IL-2 and IFN-γ production. The pathological grade of rejection was low in the transfection group. Conclusion Recipient-derived imDC transfected with IKK2dn and loaded with donor splenocyte lysate could prolong the renal allograft survival in rats probably by down-regulating the expression of DC costimulatory molecules and inhibiting the T_H 1 cytokine production.