CULTURED EPIDERMAL GRAFTS FOR BURN PATIENTS

培养的同种异体真皮移植促进部分创面快速愈合 伤口。我们开发了培养的表皮的超低温保存程序。 从仓库中取出时成功移植的同种异体移植物 烧焦的病人身上。我们还使用了正丁酸钠(NAB)(一种强烈的 角质形成细胞分化的促进剂)诱导成角质层 移植前的体外培养。NAB诱导协议已经演变成一种 模型系统，使我们能够识别潜在的正向调节器(在 特别是纤溶酶原激活物抑制物-1[PAI-1]，转化 终末分化中的生长因子β[转化生长因子-β]和c-fos 角质形成细胞。培养的同种异体表皮移植物不会在伤口上存活 床。它们的有效性可能部分归因于生产和交付。 生长因子和纤溶酶原激活物-1到伤口床。我们建议继续 细胞分化调控的分子机制分析 培养的表皮，并确定分子和生化如何 PAI-1和c-fos表达的紊乱影响随后的能力 培养的移植物可促进体内创面愈合。我们的长期目标是 提高适合移植的培养表皮的可用性和质量 异体移植。我们的具体目标是： 一、冷冻保存效果的临床研究 培养的表皮。 二、开展NAB分化能力的临床评估 培养的表皮移植物在体内起移植的作用。 三、确定外源性PAI-1可诱导的程度：(A) 角质形成细胞的生长和分化；(B)细胞骨架的重组 肌动蛋白和细胞外基质的稳定；以及(C)移植- 适宜培养的表皮移植物。 利用分子遗传学方法特异性地改变 角质形成细胞PAI-1和FOS的表达及临床意义 这种扰动对角质形成细胞分化的影响 在活体内。

Cultured epidermal allografts promote rapid healing of partial-thickness wounds. We developed procedures for cryopreservation of cultured epidermal allografts which, when retrieved from storage, were successfully grafted onto burn patients. We also used sodium n-butyrate (NaB) (a strong promoter of keratinocyte differentiation) to induce a stratum corneum in vitro prior to grafting. The NaB - induction protocol has evolved into a model system which allowed us to identify potential positive regulators (in particular, plasminogen activator inhibitor type-1 [PAI-1], transforming growth factor beta [TGF-beta] and c-fos) of terminal differentiation in keratinocytes. Cultured epidermal allografts do not persist on the wound bed. Their effectiveness may be due, in part, to production and delivery of growth factors and PAI-1 to the wound bed. We propose to continue analysis of the molecular mechanisms which regulate differentiation of cultured epidermis and to determine how molecular and biochemical perturbation of PAI-1 and c-fos expression affect the subsequent ability of cultured grafts to enhance wound healing in vivo. Our long-term goal is to improve availability and quality of transplant-suitable cultured epidermal allografts. Our specific aims are: I.To conduct a clinical study on the effectiveness of cryopreserved cultured epidermis. II.To begin clinical assessments on the ability of NaB-differentiated cultured epidermal grafts to function as transplants in vivo. III.To determine the extent to which exogenous PAI-1 can induce: (A) keratinocyte growth and differentiation; (B) reorganization of cytoskeletal actin and stabilization of the extracellular matrix; and (C) transplant- appropriate cultured epidermal grafts. IV.To utilize molecular genetic approaches to specifically alter expression of PAI-1 and fos in cultured keratinocytes and to assess the effects of such perturbations on keratinocyte differentiation in vitro and in vivo.