Lu Helen H, Spalazzi Jeffrey P
Biomaterials and Interface Tissue Engineering Laboratory, Department of Biomedical Engineering, Columbia University, 1210 Amsterdam Avenue, New York, NY 10027, USA.
Comb Chem High Throughput Screen. 2009 Jul;12(6):589-97. doi: 10.2174/138620709788681925.
The emphasis in the field of orthopaedic tissue engineering is on imparting biomimetic functionality to tissue engineered bone or soft tissue grafts and enabling their translation to the clinic. A significant challenge in achieving extended graft functionality is engineering the biological fixation of these grafts with each other as well as with the host environment. Biological fixation will require re-establishment of the structure-function relationship inherent at the native soft tissue-to-bone interface on these tissue engineered grafts. To this end, strategic biomimicry must be incorporated into advanced scaffold design. To facilitate integration between distinct tissue types (e.g., bone with soft tissues such as cartilage, ligament, or tendon), a stratified or multi-phasic scaffold with distinct yet continuous tissue regions is required to pre-engineer the interface between bone and soft tissues. Using the ACL-to-bone interface as a model system, this review outlines the strategies for stratified scaffold design for interface tissue engineering, focusing on identifying the relevant design parameters derived from an understanding of the structure-function relationship inherent at the soft-to-hard tissue interface. The design approach centers on first addressing the challenge of soft tissue-to-bone integration ex vivo, and then subsequently focusing on the relatively less difficult task of bone-to-bone integration in vivo. In addition, we will review stratified scaffold design aimed at exercising spatial control over heterotypic cellular interactions, which are critical for facilitating the formation and maintenance of distinct yet continuous multi-tissue regions. Finally, potential challenges and future directions in this emerging area of advanced scaffold design will be discussed.
骨科组织工程领域的重点在于赋予组织工程化骨或软组织移植物仿生功能，并使其能够应用于临床。实现移植物功能扩展的一个重大挑战是设计这些移植物彼此之间以及与宿主环境的生物固定。生物固定需要重建这些组织工程化移植物上天然软组织与骨界面固有的结构 - 功能关系。为此，必须将策略性仿生学纳入先进的支架设计中。为了促进不同组织类型（如骨与软骨、韧带或肌腱等软组织）之间的整合，需要一种具有不同但连续组织区域的分层或多相支架来预先构建骨与软组织之间的界面。以前交叉韧带与骨的界面作为模型系统，本综述概述了用于界面组织工程的分层支架设计策略，重点是确定从对软 - 硬组织界面固有的结构 - 功能关系的理解中得出的相关设计参数。设计方法首先着眼于解决体外软组织与骨整合的挑战，然后随后专注于体内相对较容易的骨与骨整合任务。此外，我们将综述旨在对异型细胞相互作用进行空间控制的分层支架设计，这对于促进不同但连续的多组织区域的形成和维持至关重要。最后，将讨论这一先进支架设计新兴领域中的潜在挑战和未来方向。
