Experiment Research On Immunology Of Tracheal Allotransplantation With Cryopreserved Grafts

Experiment artmcal or autogenous tracheal replacement or tracheal transplantation have been tried in the research field on the repair to the damage inflicted to long portions of the trachea, however, the tracheal transplantation has been seen as the most promising procedure. Since the trachea has antigenicity, like other organs, the fresh allografts will fail due to rejection, but immunosuppressive therapy is undesirable for many reasons, especially because the principal need for tracheal replacement is extensive carcinoma (adenoid cystic and squamous cell). In recent years, cryopreserved allografts transplantation seems to be focused for the grafts' survival without immunosuppressive therpy. Some author reported that cryopreservation could inhibit allogenicity and enlong the survival time of tracheal allografts. In our previous experiments, the canine and rabbit implanted cryopreserved tracheal allogrfts survived for a longer time (for 6 months) with weak rejection than that implanted fresh allografts. However, the reason of cryopreservation inhibiting the allogenicity of tracheal grafs and the rejection character of cryoperserved allografts are still unclear and arguments exist.For the purpose of mentioned above, we underwent the following experiments:In the first experiment, the closed colony Wister rats' orthotopic tracheal segments were programmed frozen in cryoprotective agent and stored in liquid nitrogen, then they were thawed after 1 month. In the experiment, fresh, tracheal tissue was used as controls. Analyses were performed by flow cytometry in quantu about the change of specific marker(OX-62) on tracheal dendritic cells membrane and co-stimulate molecular CD-80 and CD-86 on APCs of the cryopreserved tracheal tissue; the morphological change of tracheal DCs in situ were observed by immunohistochemical staining; and the ultrastructure of DCs were studied...