Rapid creation of autologous skin substitutes for wound repair

描述(由申请人提供)：大面积烧伤创面的修复和管理长期以来一直是一个问题和挑战。自体移植物在烧伤治疗中应用较多，但由于自体移植物供区有限，造成二次创面，限制了自体移植物在大面积烧伤中的广泛应用。自体组织工程皮肤替代物(ATESS)被认为是最有前途的自体移植替代材料。它们具有自体移植物的许多特性，如伤口保护、加速伤口闭合、移植物接合率高、新皮肤再生和无免疫排斥。使用ATESS进行大面积烧伤治疗，有两个关键问题尚未解决：1)创造皮肤替代物的体外时间应尽可能短，以允许创面快速愈合；2)ATESS的大小应尽可能大，以覆盖足够的创面。目前的组织工程方法需要较长的培养时间，而且不能产生大量的皮肤替代物。因此，开发新的方法和策略来快速生产具有放大潜力的自体皮肤替代品是可取的。我们研究的主要目标是开发一种新的实用协议，使用纳米纤维启用的逐层细胞组装方法来快速创建ATESS。我们的具体目标是：1)利用皮肤细胞逐层组装的方法在体外制备和表征皮肤替代物；2)在小鼠模型上测定组织工程皮肤替代物对急性全层创面愈合的影响。这些研究将有助于开发一种实用的治疗方案，用于急性或烧伤伤口的修复和再生。与公共健康相关：这项建议旨在建立一种创新的方法，利用纳米纤维辅助的逐层细胞组装来构建皮肤替代品，并评估组装的构建体的体外开发及其在全层伤口修复中的体内应用。这种方法允许我们在收集纳米纤维的过程中，通过直接将皮肤细胞与仿生纳米纤维组装在一起，快速(在一周内甚至一夜之间)创造出任何大小的自体皮肤替代品。因此，它将显著缩短体内植入前的体外时间。自体皮肤替代物的快速产生将使创面快速闭合，因此，将适合于大面积烧伤创面的治疗。此外，这种新的方法可以很容易地适应于其他类型的层状组织的组织工程。这将加速组织工程产品在医疗保健服务中的广泛应用。

DESCRIPTION (provided by applicant): The repair and management of extensive burn wounds have long been a problem and challenge. Autografts are often used in the burn treatment; however, limited supply and the creation of secondary wound by harvesting autografts hold its wide application for extensive burns. Autologous tissue engineered skin substitutes (ATESS) are considered the promising alternative to autografts. They possess many of the properties of an autograft, such as wound protection, accelerated wound closure, high graft take, new skin regeneration, and no immunorejection. For extensive burn treatment using ATESS, there are two unsolved and critical issues: 1) the in vitro time to create skin substitutes should be as short as possible, allowing rapid wound closure; 2) the size of ATESS should be as large as possible to cover enough wounded area. Current tissue- engineering approaches require prolonged culture time and cannot produce large skin substitutes. Therefore, it is desirable to develop new approaches and strategies toward rapid production of autologous skin substitutes with up-scaling potential. The primary objective of our research is to develop a novel practical protocol for rapid creation of ATESS using a nanofiber-enabled layer-by-layer cell assembly approach. Our specific aims are: 1) in vitro preparation and characterization of skin substitutes using layer-by- layer assembly of skin cells, 2) in vivo determination of the effect of tissue engineered skin substitutes on the healing of acute full-thickness wounds in a mouse model. These studies will help to develop a practical therapeutic protocol for acute or burn wound repair and regeneration. PUBLIC HEALTH RELEVANCE: This proposal is to establish an innovative approach to construct skin substitutes using layer-by-layer cell assembly with the assistance of nanofibers and evaluate the in vitro development of the assembled construct and its in vivo application for full-thickness wound repair. This approach allows us to rapidly (within one week or even overnight) create autologous skin substitutes of any size by directly assembling skin cells with biomimetic nanofibers during the collection of nanofibers. As a result, it will significantly shorten the in vitro time prior to in vivo implantation. The rapid creation of autologous skin substitutes will enable the quick closure of wound and, therefore, will be suitable for the treatment of extensive burn wounds. Additionally, this new approach can be easily adapted to tissue engineering of other types of layered tissues. This will accelerate the wide applications of tissue-engineered products in health care delivery.