摘要
目的 探讨深低温冻储对气管移植物树突状细胞的影响。方法 将 5 0段Wister大鼠气管 (4个环 )随机分为新鲜对照组和深低温冻储组 ,通过流式细胞技术、免疫组化技术和透射电镜技术 ,观察树突状细胞冻储前后变化。结果 ①深低温冻储后气管组织制备的单细胞悬液OX - 6 2FITC标记率和表达量下降 ,显著低于新鲜对照组 (P <0 .0 0 0 1)。②免疫组化染色结果显示 ,冻储后气管树突状细胞肿胀、树突远端淡染、细胞分布稀疏。③透射电镜观察 ,树突状细胞经冻储 1个月后出现空泡变性、溶酶体变性、酶活性减弱。结论 树突状细胞主要分布于气管上皮及混合腺内 ,冻储过程损伤气管移植物树突状细胞 ,造成树突状细胞数量减少和功能下降 ,这可能是气管移植物冻储后 ,免疫原性下降的一个重要原因。
Objective To investigate the influence of cryopreservation on tracheal dendritic cells. Methods Fifty Wister rats′ orthotopic tracheal segments were divided into fresh group and cryo-group, and the fresh group was used as control. Analyses were performed by flow cytometry in quantity about the change of specific marker(OX-62) on tracheal dendritic cells membrane; the morphological change of tracheal DCs in situ were observed by immunohistochemical staining; and the ultrastructure of DCs were studied by transmitted electron microscopy. Results Compared with DCs in single cell suspensions of fresh trachea, the DCs in cryopreserved trachea had decreased percentage of cells and weakly expressed OX-62, and there was statistic significance in the difference. Immunostained DCs in cryopreserved trachea showed that cells were swelling or the distal parts of dendritic process were stained light and density was thin. Observed by transmitted electron microscopy, the DCs in cryopreserved trachea displayed vacuolation, degeneration of lysosomes and decresed enzyme activity. Conclusion The dendritic cells mainly distribute in tracheal epithelium and mixed glands. Because of damage during cryopreservation, the number and activity of DCs in tracheal grafts decreased. It could be one of important reasons contributing to the decreasing allogenicity of tracheal allografts after cryopreservation.
关键词
深低温冻储
气管移植
树突状细胞
Cryopreservation
Tracheal transplantation
Dendritic cell
