转化生长因子-β1基因修饰未成熟树突状细胞诱导大鼠肝移植免疫耐受

The effect of immature dendritic cells modificated with transforming growth factor-IS1 on immune tolerance in the rat liver transplatation

目的观察转化生长因子-β1（TGF-β1）基因转染未成熟树突状细胞（imDC）对大鼠肝移植免疫耐受的诱导作用。方法利用大鼠骨髓细胞诱导培养imDC，以脂质体介导的pIRES2-EGFP—hTGF—Bl转染imDC，于移植前5d输注受体Lewis大鼠体内，移植后分别于3、7、10d抽血检测肝功能[总胆红素（TBIL）和谷丙转氨酶（ALT）]、酶联免疫吸附试验（ELISA）法检测白细胞介素-12（IL-12）水平、肝组织苏木素-伊红（HE）染色急性排斥反应病理评分、原位末端转移酶标记（TUNEL）法检测肝脏淋巴细胞的凋亡及观察各组大鼠肝移植后的生存时间。结果TGF-β1组移植后肝功能（TBIL和ALT）优于各对照组（P〈0．05）；TGF—β1组移植后3、7d血清IL-12浓度分别为71．03±10．70、80．88±14．23均低于各对照组（P〈0．05）；TGF-β1组移植后7d出现交界性排斥反应，移植10d后出现轻度排斥反应（P〈0．05）；TGF-β1基因转染组移植后3、7、10d汇管区淋巴细胞凋亡指数分别为6．75±1．93、14．00±2．19、18．25±1．38，较各对照组均明显增高（P〈0．05）；TGF-β1组大鼠移植后中位生存期为58d，明显长于各对照组。结论TGF—β1基因改造的imDC能诱导大鼠移植免疫耐受，在诱导器官移植耐受中有良好时应用前景。

Objective To assess the effect of immature dendritic cells （imDCs） modificated with transforming growth factor-β1 （ TGF-β1 ） on immune tolerance in a rat liver transplantation. Methods The animals were divided into allogenic transplantation, imDC, mature dendritic cell （mDC） , plRES2- EGFP, and TGF-β1. Rat bone marrow-derived imDCs were obtained after primary culture of bone marrow cells in RPMI 1640 medium with different cytokines. ImDCs transfected with plasmid vectors encoding TGF-β1 were injected into the allogenie Lewis rat 5 days before liver transplantation. Liver functions [ total bilirubin （TBIL） and alanine aminotransferase （ALT） ], interleukin （IL）-12 level in the blood, liver pa- thology by hematoxylin and eosin （HE）. staining, acute liver rejection grades valued by Baff standard, apoptosis of lymphocyte in recipient liver analyzed by Tunnel staining, and survival time were observed 3 d, 7 d and 10 d post liver transplantation respectively. Results TBIL and ALT were much lighter in Group TGF-β1 than control groups（P 〈0.05）. The level of IL-12 [ （71.03±10. 70）, （80. 88±14. 23） μg/L respectively] in 3,7 d after liver transplantation is much lower in Group TGF-β1 than control groups （P 〈 0. 05）. Apoptosis of T cells in 3, 7, 10 d after liver transplantation （6. 75 _＋ 1.93, 14. 00 ±2. 19, 18.25±1.38） is much more in group TGF-β1 than control groups. Light acute rejection was observed in TGF-β1 group in 10 d after liver transplantation（ P 〈 0.05 ）. The medium survival time is about 58 day, which is longer than in control groups （ P 〈 0. 05 ）. Conclusion ImDCs modificated with TGF-β1 can enhance the immue tolerogenicity in a rat liver transplantation, it might be a promising therapy for donor-specific toler- ance after organ transplantation.