转化生长因子β1质粒对新鲜同种异体骨移植的免疫影响

Immune Effects of Transforming Growth Factorβ1 on Allograft-Bone Transplantation in Rats

目的:研究局部含注射转化生长因子β1(TGF-β1)基因的质粒对大鼠同种异体骨移植的免疫排斥反应的影响。方法:将64只Wister大鼠完全随机分成4组,每组16只,切取SD大鼠的胫骨移植到Wister大鼠人工建模后形成的胫骨缺损区。TGF-β1组于移植骨局部一次性注射含有TGF-β1基因的质粒(40μg/只);空质粒组于移植局部注射空质粒;免疫抑制剂组术前3天开始腹腔内注射环孢素A(10mg/kg)直至处死;异体移植组仅行异体骨移植,不予特殊处理。术后3、6、12周行光镜和电镜检查。结果:异体移植组和空质粒组骨基质排列紊乱,骨细胞消失,基质区内见块状低电子密度区。TGF-β1组和免疫抑制剂组可见骨细胞和完整的成骨细胞,骨小管状态良好。混合淋巴细胞培养(MLC)结果显示TGF-β1组(0.331±0.017)与免疫抑制剂组(0.501±0.004)差异无统计学意义(P>0.05),TGF-β1组与空质粒组(1.104±0.023)和异体移植组(1.206±0.019)差异有统计学意义(P<0.05)、结论:新鲜骨移植过程中局部注射TGF-β1质粒可发挥免疫抑制作用,降低宿主的免疫排斥反应。

Objective： To investigate the immune effects of transforming growth factor-β1 （TGF-β1） on allografl-bone transplantation in rats by local injection. Methods： Sixty-four Wister rats were divided into 4 groups （16 rats each ）. Rats in TGF-β1 gene plasmid group were transplanted with tibia of SD rats which were about 1 cm, and then give the injection of 40μg TGF-β1. Rats in without gene plasmid group were given local injection of 40μg empty plasmid once. Those rats in the immunosuppressant group were administrated Cyclosporine A （10 mg/kg） one time per day from the third day before transplantation till sacrificed. Rats in allotransplant group were transplanted with tibia of SD rats, without other treatment. The artery at 3,6,12 weeks after surgery were tested by imaging, histology and Immunological assays of these groups. Results： In allograft and blank plasmid group, bone matrix were disordered, bone cells disappeared, and there was low electron density in the region. In TGF-β1 and immune inhibitor group, there were complete bone cells in bone canaliculi in good condition. Mixed lymphocyte culture （MLC） showed that there was no difference between TGF-β1 group （0.331 ±0.017） and immunosuppressant group （0.501 ±0.004） （P〉0.05）, while it was significantly between TGF-β1 group and allogeneic transplantation group （1.206 ±0.019） （P〈0.05）. Conclusion： TGF-β1 could play immunosuppressive effects on fresh bone transplantation by reducing the host immune rejection.