复合环孢菌素同种异体骨的免疫学与组织学评价

Immunologic and histoiogic evaluations of the cyciosporine-impregnated aliograft bone

目的对比评价复合环孢菌素同种异体骨（CAB）的免疫学特性及成骨特性。方法54只新西兰兔随机分为三组（每组18只）：实验组（植入CAB修复兔桡骨中段骨缺损）、对照组（植入深冻／冻干辐照同种异体骨修复兔桡骨中段骨缺损）、材料提供组。于不同时间点抽血行淋巴细胞亚群分析并取材，标本经处理后分别行CD25分子免疫组化染色和改良马松三色法染色并图像分析，对淋巴细胞亚群及新骨面积行统计学分析。结果术后16周对照组CD25分子密度明显高于实验组，且对照组各个时间点间的CD4^＋T淋巴细胞百分数及CD8^＋T淋巴细胞百分数波动明显，差异有统计学意义（P〈0．05）；实验组各骨缺损修复部位新骨生成面积均大于对照组，差异有统计学意义（P〈0．001）。结论免疫学及组织学结果初步显示，与深冻／冻干辐照同种异体骨相比，CAB可以更稳定持久地抑制免疫排斥反应并更好地促进新骨生成。

Objective To compare the cyclosporine-impregnated allograft bone with the deep-frozen/freeze-dried irradiated bone allograft with respect to immunosuppression and bone-healing promotion. Methods Cyclosporine-impregnated bone allograft was implanted to repair segmental defects of right radius in 18 New Zealand Rabbits in the study group while the deep-frozen/freeze-dried irradiated bone allograft in 18 rabbits in the control group. At preoperative day 1 and postoperative weeks 1, 4 and 16, a total of 6 animals in each group were used to determine the changes of T lymphocyte subsets （CD4^＋ and CD8^＋） in peripheral blood by flow cytometry. At postoperative weeks 1, 4 and 16, respectively, 6 animals in each group were sacrificed to harvest their right radii repaired. In the radial samples, CD25 molecules were stained by immunohistochemistric method, and areas of new bone were assessed by means of histology and image analysis. Results At postoperative week 16, the density of CD25 molecules, the percentages of CD4^＋ T and CD8^＋ T lymphocytes and the ratios of CD4^＋ T/CD8^＋ T, were found higher in the control group than in the study group （P 〈 0. 05） . The areas of new bone in the study group were larger than those in the control group, with significant differences in all regions between the 2 groups（ P 〈 0. 001 ） . Conclusion The cyclosporine-impregnated allograft bone is superior to the deep-frozen/freeze-dried irradiated allograft bone in terms of immunosuppression and bone-healing promotion.