小鼠同种气管异位移植建立闭塞性细支气管炎动物模型

Establishment of Obliterative Bronchiolitis Model by Heterotopic Trachea Allograft Transplantation in Mice

目的闭塞性细支气管炎(OB)是临床肺移植后主要致死因素且发病机制不清,拟用小鼠气管异位移植模拟OB的病变过程,为研究OB提供动物模型。方法将小鼠分成同基因移植对照组(BALB/C→BALB/C)与异基因移植实验组(BALB/C→C57BL/6)两大组,供体小鼠气管移植到受体小鼠背部两侧皮下,术后3、7、14、21、28 d取出气管移植物,苏木精-伊红染色观察比较组织形态改变,统计分析其上皮覆盖率和管腔闭塞率。结果共完成70例小鼠气管同种异位移植手术,手术成功率94.3%。不同取材时间,同基因对照组和异基因实验组气管移植物苏木精-伊红染色有不同改变,其中以术后21 d实验组气管移植物OB改变最为典型,而对照组气管移植物组织结构基本正常,此时上皮覆盖率两组分别为:0%和(92±6)%,管腔闭塞率两组分别为:(73±12)%和<3%,差异均有显著性意义。结论小鼠气管异位移植成功模拟肺移植后OB的病变过程,术后21 d可作为研究OB的重要时间点。手术操作简便,成功率高,技术稳定。适用于临床肺移植术后OB的发病机制和治疗学的研究。

Objective To establish an easier and effective animal model of obliterative bronchiolitis （OB） by heterotopic trachea allo-transplantation in mice. Methods The mice were divided into two groups： allo-transplantation as experimental group （BALB/C→CS7BL/6） and iso-transplantation as control group （BALB/C→BALB/C）. Tracheas from 140 mice were implanted subcutaneouly in the back of 70 recipient mice. The grafts were removed on the day 3, 7, 14, 21 and 28 after transplantation and stained with hematoxylin and eosin. Visual and morphometric analyses of the airway grafts were performed to evaluate the extent of airway obliteration, luminal coverage by respiratory or flattened cuboidal epithelium, and extent and density of peritracheal cellular inflammation. Results Heterotopic trachea transplantation was performed on 70 mice, and success rate was 94.3%0 （66/70）. All the allografts of the experimental groups were different from the isografts of the control groups at every time point. It was found that the day 21 after transplantation was the critical time point for OB formation： the allograft showed typical OB with obliterative intraluminal fibroproliferation, complete loss of epithelium and substantial inflammatory infiltration, while the isografts showed almost normal histological structure. In experimental group and control group, the epi- thelial coverage was 0 vs （92±6）%, and the luminal obliterative ratio was （73±12） % vs 〈3% （P〈0.01）. Conclusion The model for OB after tracheal allograft transplantation in mice undergoes tracheal obliteration with histologic features of OB in human tung transplant recipients. The operation is simple and success rate is high. The model is practical in the study of chronic rejection of lung transplantation and deserves to popularize.