Purpose: Tracheal transplantation is necessary in patients with extensive tracheal stenosis caused by trauma, congenital disease, benign or malignant tumor. Results with the cryopreserved vascular homograft have prompted us to evaluate
cryopreserved trachea. When trachea is cryopreserved, it maintains viability of the cartilage and allogenicity decreased because epithelium of trachea whitch has major allogenicity (MHC class Ⅱ Antigen) is exfoliated after some periods of
cryopreservation. We assessed the proper duration of cryopreservation and probability of trachea allotransplantation.
Methods: The trachea were harvested from Mongrel dogs and frozen to 80℃ for different length preservation (group 1: 1∼10 week, group 2: 1 month, 2 months, 3 months, 6 months, 2 months). Ggoup 1 was thawed and tested epithelial viability,
Group
2 was perfomed trachea transplantation with cryopreserved trachea allograft, after one months We checked gross appearance, viability of cartilage and grade of monocyte infiltration (rejection).
Results: In group 1, Exfoliation of epithelium was begun after four weeks cryopreservation, in group 2, when allograft was extracted, trachea of 4 dogs was stenosed, and six months preserved trachea was not seen due to total necrosis.
Cartilage
viability of 4 case of transplantation, three of 4 case were mild infiltration of monocyte.
Conclusion: We conclude that more than 1 month cryopreservation for prevention of rejection and additional procedure (omentopexy) for graft vascular supply are needed for trachea transplatation. Although cryopreservation was performed, all
case
of transplantation happened some degree graft rejection. if trachea transplantation will be applied, immune suppress will be needed.
|