Cryopreservation alters antigenicity of allografts in a porcine model of transplant vasculopathy

• Published in: Transplantation proceedings Vol. 36; no. 10; pp. 3288 - 3294
• Main Authors: Solanes, N., Rigol, M., Castellà, M., Khabiri, E., Ramı́rez, J., Segalés, J., Roqué, M., Agustı́, E., Pérez-Villa, F., Roig, E., Pomar, J.L., Sanz, G., Heras, M.
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01.12.2004; Elsevier Science
• Subjects: Animals; Biological and medical sciences; Coronary Vessels - drug effects; Coronary Vessels - immunology; Coronary Vessels - transplantation; Cryopreservation - methods; Cyclosporine - pharmacology; Fundamental and applied biological sciences. Psychology; Fundamental immunology; Granulocytes - immunology; Immunosuppressive Agents - pharmacology; Isoantigens - immunology; Macrophages - immunology; Medical sciences; Models, Animal; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Swine; Tissue, organ and graft immunology; Transplantation, Autologous; Transplantation, Homologous - immunology; Tunica Intima - immunology; Tunica Media - immunology; Homograft; Transplantation; Pig; Medicine; Graft vascular disease; Vertebrata; Mammalia; Treatment; Antigenicity; Cryopreservation; Surgery; Animal; Graft; Models; Artiodactyla; Ungulata
• ISSN: 0041-1345; 1873-2623
• DOI: 10.1016/j.transproceed.2004.10.053

The need for arterial grafts in coronary surgery to complement autologous vessels has generated interest in cryopreservation of small diameter allografts. We evaluated functional and histologic changes occurring in cryopreserved allografts 3 months after porcine femoral artery transplants. Twenty recipient and 15 donor pigs included a control group of 16 fresh and 12 cryopreserved nonimplant arteries were used. Fresh ( n = 5) and cryopreserved ( n = 5) autografts were implanted to assess cryopreservation effects in the absence of rejection. Fresh allografts with or without treatment with cyclosporine (CsA) ( n = 6 of 8) and cryopreserved allografts with or without treatment with CsA ( n = 6 of 10) were performed to study the antigenicity of cryopreserved allografts. Arteries were stained with hematoxylin and eosin, Masson's trichrome, and orcein for morphometric analyses and immunostained to identify endothelial cells, smooth muscle cells, T lymphocytes, and macrophages. Among nonimplant arteries, cryopreservation reduced α-actin expression and increased the luminal area. All implanted autografts were patent. Cryopreserved autografts showed reduced α-actin expression and developed intimal hyperplasia compared to fresh autografts. Treatment with CsA improved the patency of fresh allografts from 0% to 83% ( P < .01) and of cryopreserved allografts from 40% to 100% ( P < .05). Cryopreserved allografts showed substantial intimal hyperplasia, and fresh allografts had more T lymphocyte infiltration in the intimal layer with aneurysmal dilatation. Cryopreservation reduces the deposition of inflammatory cells and prevents the thrombosis or aneurysmal lesions observed in fresh allografts. Therefore, cryopreservation modifies the antigenicity of vascular allografts.