Histologieal Comparison of Low Temperature Preservation and Cryopreservation of the Aorta / 日本心臓血管外科学会雑誌

ABSTRACT

The surgical replacement of human vessels or valves using allografts (homografts) has been reported as a useful method. Nevertheless, little is known about preservation effects and immunological consequences using low temperature preservation and cryopreservation. In this study, we examined the histological changes and immunological changes of cryopreserved aorta in a rat model, and compared the results with those of low temperature preserved aorta. Ascending aorta was harvested from Wister-King rats and preserved in TC199 solution at 4°C (low temperature preservation group) and cryopreserved (cryopreservation group) for 1, 2, and 3 weeks. The preserved aorta was then transplanted to the abdominal aorta of the recipient rat. The graft patency and histology, including immunohistochemical stain (IgG, IgM, C3), were assessed at 3 weeks after transplantation. In the cryopreservation group prominent intimal thickness was observed. However, cell infiltration from adventitia was observed in the low temperature preservation group. Immunohistochemical stains indicated the deposit of immunoglobulin was seen after transplantation in both groups. The result of this study suggested that successful preservation of aorta was possible at one week with low temperature preservation and 3 weeks with cryopreservation in the rat model.