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处理一直是一个难题和挑战。自体移植物常用于烧伤治疗；然而，有限的供应和二次创面产生的收获自体移植物限制了其广泛应用于大面积烧伤。自体组织工程皮肤替代物（ATESS）被认为是一种很有前途的自体植皮替代物。它们具有自体移植物的许多特性，如伤口保护，加速伤口愈合，高移植率，新皮肤再生，无免疫排斥。对于使用ATESS进行大面积烧伤治疗，有两个尚未解决的关键问题：1)体外制造皮肤替代品的时间应尽可能短，以便快速愈合伤口；2) ATESS的尺寸应尽可能大，以覆盖足够的受伤区域。目前的组织工程方法需要较长的培养时间，不能产生大的皮肤替代品。因此，需要开发新的方法和策略来快速生产具有扩大规模潜力的自体皮肤替代品。我们研究的主要目标是开发一种新的实用方案，使用纳米纤维支持的逐层细胞组装方法快速创建ATESS。我们的具体目标是：1)利用皮肤细胞逐层组装在体外制备和表征皮肤替代品，2)在体内确定组织工程皮肤替代品对小鼠急性全层伤口愈合的影响。这些研究将有助于制定一种实用的治疗方案，用于急性或烧伤伤口的修复和再生。公共卫生相关性：本提案旨在建立一种创新的方法，在纳米纤维的帮助下，利用细胞逐层组装构建皮肤替代品，并评估组装结构的体外发展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直接将皮肤细胞与仿生纳米纤维组装在一起，从而快速（在一周内甚至一夜之间）制造出任何大小的自体皮肤替代品。因此，在体内植入之前，它将显著缩短体外时间。自体皮肤替代物的快速产生将使伤口快速闭合，因此，将适用于大面积烧伤伤口的治疗。此外，这种新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.