HBsAg-树突状细胞疫苗对肝移植后免疫抑制状态大鼠抗-HBs产生的影响

Effects of HBsAg pulsed dendritic vaccination on anti-HBs production in immunosuppressed rats after liver transplantation

目的 观察乙型肝炎表面抗原（HBsAg）冲击的树突状细胞（DCs）疫苗对肝移植（LT）术后处于免疫抑制状态大鼠的抗HBs产生的影响。方法Lewis大鼠LT术后（BN大鼠为供体）给予大剂量他克莫司（FK506，2mg／kg），建立LT术后免疫抑制状态的动物模型，并随机分为两组。术后14d及28d，经腹腔注入HBsAgDCs疫苗者为HBsAg—DCs组（15只），连续观察12周，注入HBsAg疫苗200ul者为HBsAg组（15只）；未子免疫抑制的LT术后Lewis大鼠为对照组（5只）。切取肝脏组织行光、电镜检查；RT—PCR检测脾脏白细胞介素（IL）2、干扰素（IFN）YmRNA表达水平；酶联免疫吸附法检测血清IL-2、IFNy及抗HBs水平。两组间比较采用t检验，多组间比较采用单因素方差分析。结果大剂量FK506使HBsAgDCs组及HBsAg组动物处于高度免疫抑制状态，肝脏无排斥反应、IL2及IFNY表达水平明显低于对照组，t值为21．35～48．74，P值均〈0．05；HBsAg—DCs组在疫苗注射后1、2、3个月均能检测到高滴度的抗HBs，分别为（255．24±34．16）IU／L、（145．11±12．37）IU／L、（185．43±17．18）IU／L，明显高于HBsAg组（抗-HBs几乎为0），t值分别为45．24、47．69、58．38，P值均〈0．05。结论在LT术后处于免疫抑制状态的大鼠体内，HBsAg—DCs疫苗仍能诱导出高血清滴度的抗HBs。

Objective To explore the effects of HBsAg pulsed dendritic vaccination on anti-HBs production in immunosuppressed rats after liver transplantation （LT）. Methods Brown-Norway liver allografts were transplantated into Lewis reipients. The transplantated Lewis rats were injected with EKS06 （2 mg/kg） and randomly divided into two groups： rats in HBsAg-DCs group （n = 15） were intraperitoneally injected with HBsAg pulsed DCs at 14 d and 28 d after LT, and rats in the HBsAg group （n = 15） were injected with HBsAg （200 μl） once a week for 12 weeks. Rats without any immunosuppressive treatment after LT served as controls （n= 5）. IL-2 and IFN y mRNA expression in spleen were analyzed by RT-PCR, serum IL- 2, IFN y and anti-HBs were detected by ELISA. Results High dose of FK506 resulted in the immunosuppressed in LT rats, as evident by low production of IL-2 and IFN y, and without liver rejection compared to rats in the control group. HBsAg-DCs induced high titer of anti-HBs antibody, however, titer of anti-HBs were seldom detectable in the HBsAg group at 1, 2 and 3 mouth after vaccination. Conclusion The capacity of HBsAg-DCs to induce anti-HBs in immunosuppressed rats suggested that DC vaccine may orevent HBV recurrence in liver transplantated patients.