Schmidt C E, Baier J M
Department of Chemical Engineering, University of Texas at Austin, 78712, USA.
Biomaterials. 2000 Nov;21(22):2215-31. doi: 10.1016/s0142-9612(00)00148-4.
Various research groups around the world are actively investigating cardiovascular prostheses of biological origin. This review article discusses the need for such bioprosthetics and the potential role for natural tissues in cardiovascular applications such as cardiac valves and vascular grafts. Upon implantation, unmodified natural materials are subject to chemical and enzymatic degradation, seriously decreasing the life of the prosthesis. Therefore, methods such as glutaraldehyde and polyepoxide crosslinking treatments and dye-mediated photooxidation have been developed to stabilize the tissue while attempting to maintain its natural mechanical properties. Also, residual cellular components in a bioprosthetic material have been associated with undesired effects, such as calcification and immunological recognition, and thus have been the motivation for various decellularization processes. The effects of these stabilization and decellularization treatments on mechanical, biological and chemical properties of treated tissues have been investigated, specifically with regard to calcification, immunogenicity, and cytotoxicity concerns. Despite significant advances in the area of cardiovascular prostheses, there has yet to be developed a completely biocompatible, long-lasting implant. However, with the recent advent of tissue engineering, the possibility of applying selective cell seeding to naturally derived bioprosthetics moves us closer to a living tissue replacement.
世界各地的多个研究小组正在积极研究生物源心血管假体。这篇综述文章讨论了此类生物假体的需求以及天然组织在心脏瓣膜和血管移植物等心血管应用中的潜在作用。植入后，未经修饰的天然材料会受到化学和酶促降解，严重缩短假体的使用寿命。因此，已开发出诸如戊二醛和聚环氧化物交联处理以及染料介导的光氧化等方法来稳定组织，同时试图保持其天然机械性能。此外，生物假体材料中的残留细胞成分与诸如钙化和免疫识别等不良影响有关，因此成为各种去细胞化过程的动因。已经研究了这些稳定化和去细胞化处理对处理后组织的机械、生物学和化学性质的影响，特别是在钙化、免疫原性和细胞毒性方面。尽管心血管假体领域取得了重大进展，但尚未开发出完全生物相容、持久的植入物。然而，随着组织工程的最新出现，将选择性细胞接种应用于天然来源生物假体的可能性使我们更接近活体组织替代物。
