Mechanisms of Wound Healing with Cultured Human Skin

培养人类皮肤的伤口愈合机制

基本信息

批准号：
6764053
负责人：
Steven T Boyce
金额：
$ 36.04万
依托单位：
UNIVERSITY OF CINCINNATI
依托单位国家：
美国
项目类别：
财政年份：
1994
资助国家：
美国
起止时间：
1994-01-01 至 2006-06-30
项目状态：
已结题

项目摘要

DESCRIPTION (provided by applicant) Rapid and effective healing of burn wounds with cultured analogs of human skin is the central objective of this proposal. Medical benefits from improved healing may include, but not be limited to; reduced requirements for split- thickness autograft, shorter hospitalization time; and reduced long-term morbidity after recovery. However, anatomic and physiologic deficiencies of all current models of cultured skin have restricted realization of these benefits. Major deficiencies result from culture conditions that do not generate an epidermal analog with fully functional barrier properties, from irregular pigmentation after healing, and from absence of a vascular plexus in the dermal analog which delays vascularization. The current model of cultured skin substitute (CSS) in this laboratory is a collagen- based sponge populated with cultured human keratinocytes and fibroblasts. An investigative cycle has been established to: A) design experiments to address clinical deficiencies of CSS, B) perform mechanistic studies in vitro to generate new prototypes of CSS; C) transplant experimental CSS to athymic mice to measure efficacy and tissue phenotypes, and, D) study the improved prototype of CSS for reduction of mortality and morbidity in critically injured burn patients. Six specific aims will be pursued: 1 ) Regulation of cellular viability (DNA synthesis, mitochondrial metabolism) and phenotypes (epidermal barrier, basement membrane) by culture conditions (media, biophysical environment); 2) Identification of molecular mediators (cytokines, extracellular matrix) of wound healing processes (angiogenesis, matrix structure); 3) Regulation of melanocyte distribution (cell density) and pigment expression (melanin content) to restore normal skin color; 4) Stimulation of angiogenesis by addition of human dermal microvascular endothelial cells and morphogenesis of vascular analogs; 5) Regulation and automation of keratinocyte growth rates and metabolism (reduction of lactic acid and ammonia) in the Kerator bioreactor; and, 6) Treatment of extensive burns with cultured skin substitutes in the clinic by paired-site comparison to meshed, split-thickness skin autograft. Comparative parameters will include: a) quantitative wound closure with skin substitutes (rates of engraftment, ratio of healed area to biopsy area, frequency of regraftng); and, b) qualitative outcome (scarring, contraction, function and cosmesis). The investigators possess all of the required expertise in cell biology, skin biochemistry and biophysics, wound physiology, chemical engineering and clinical burn care to perform these studies successfully. Accomplishment of these objectives will contribute to reduced mortality and morbidity from burns, improved materials for plastic and reconstructive surgery, and development of other tissue and organ substitutes.

描述（由申请人提供）利用培养的人类皮肤类似物快速有效地治愈烧伤伤口是本提案的核心目标。改善愈合带来的医疗益处可能包括但不限于：减少自体分层厚度的要求，缩短住院时间；并减少康复后的长期发病率。然而，当前所有培养皮肤模型的解剖学和生理学缺陷限制了这些益处的实现。主要缺陷是由于培养条件不能产生具有完全功能性屏障特性的表皮类似物、愈合后不规则色素沉着以及真皮类似物中缺乏血管丛而延迟了血管形成。该实验室当前的培养皮肤替代品 (CSS) 模型是一种基于胶原蛋白的海绵，其中填充有培养的人类角质形成细胞和成纤维细胞。已经建立了一个研究周期：A) 设计实验来解决 CSS 的临床缺陷，B) 进行体外机制研究以生成新的 CSS 原型； C) 将实验性 CSS 移植到无胸腺小鼠中，以测量疗效和组织表型，D) 研究改进的 CSS 原型，以降低严重烧伤患者的死亡率和发病率。将追求六个具体目标：1）通过培养条件（培养基、生物物理环境）调节细胞活力（DNA合成、线粒体代谢）和表型（表皮屏障、基底膜）； 2) 伤口愈合过程（血管生成、基质结构）的分子介质（细胞因子、细胞外基质）的鉴定； 3）调节黑色素细胞分布（细胞密度）和色素表达（黑色素含量），恢复正常肤色； 4) 通过添加人真皮微血管内皮细胞和血管类似物的形态发生来刺激血管生成； 5）Kerator生物反应器中角质形成细胞生长速率和代谢（乳酸和氨的减少）的调节和自动化； 6) 通过与网状、分层皮肤自体移植物的配对部位比较，在临床上用培养的皮肤替代品治疗大面积烧伤。比较参数包括： a) 使用皮肤替代物定量伤口闭合（植入率、愈合面积与活检面积的比率、再移植频率）； b) 定性结果（疤痕、收缩、功能和美容）。研究人员拥有成功进行这些研究所需的细胞生物学、皮肤生物化学和生物物理学、伤口生理学、化学工程和临床烧伤护理方面的所有专业知识。这些目标的实现将有助于降低烧伤死亡率和发病率、改进整形和重建手术材料以及开发其他组织和器官替代品。