MECHANISMS OF KERATINOCYTE MOTILITY

角质细胞运动机制

• 批准号: 6632748
• 负责人: DAVID T. WOODLEY
• 金额: $ 34.03万
• 依托单位: UNIVERSITY OF SOUTHERN CALIFORNIA
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-03-24 至 2005-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6632748
• 关键词: cell migration; cytoskeletal proteins; extracellular matrix; extracellular matrix proteins; growth factor; human tissue; hypoxia; integrins; keratinocyte; lamins; metalloendopeptidases; oxygen tension; protein isoforms; tissue inhibitor of metalloproteinases; wound healing

DESCRIPTION: (Adapted from the applicant's abstract) - Human keratinocyte motility is a critical early event in the process of wound healing. The biological elements that directly influence human keratinocyte migration are poorly understood. Moreover, the fact that keratinocyte migration must occur within the microenvironment of the healing wound dictates that experiments be designed that directly examine elements of the wound environment and evaluate how they influence the biological behavior of cells. Their assays are designed to dissect the functions of keratinocyte motility from other biological functions such as cell proliferation. Their recent work demonstrates clearly that the type of connective tissue component or components juxtaposed to the basal keratinocyte is a major influence upon inducing migration and stopping migration. In addition to extracellular matrix effects, keratinocyte migration can be influenced by selected growth factors (such as EGF, TGFA, and IL-1) but not by a number of other soluble factors (e.g., NGF, IL-8, TGFb, etc.). Hypoxia is also a major element in influencing keratinocyte migration. In human skin wounds treated with semi-permeable occlusive dressings that have been demonstrated to promote re-epithelialization and wound healing, the healing skin wound micro-environment is characterized by very low oxygen tension and low pH. In accordance with this in vivo observation, their recent preliminary observations demonstrate that keratinocytes exhibit enhanced migration under hypoxic conditions. In this proposal, they wish to explore the cellular mechanisms of human keratinocyte migration over connective tissue components. Moreover, they wish to examine these cellular mechanisms under normoxic and hypoxic conditions in order to validate their biological importance in the setting of a micro- environment akin to true wound healing. The specific aims are (i) to examine the role of laminin and laminin isoforms (laminin 5 = epiligrin, kalinin, nicein) in keratinocyte motility and determine if hypoxia alters the keratinocyte synthesis and deposition of matrix-adherence molecules, (ii) to determine the role of lamellipodia-associated proteins (ezrin, moesin, radixin) in keratinocyte migration and determine the influence of hypoxia upon the expression of these lamellipodia-associated components, (iii) to examine integrin receptors in motile and non-motile keratinocytes under normoxic and hypoxic conditions, and (iv) to examine the role of metalloproteinases and their respective inhibitors in the process of keratinocyte migration and determine if hypoxic and normoxic conditions alter their expression.

描述：（改编自申请人的摘要）- 人类 角质形成细胞运动是伤口过程中关键的早期事件 康复。直接影响人体的生物因素 人们对角质形成细胞的迁移知之甚少。此外，事实是 角质形成细胞迁移必须发生在角质形成细胞的微环境内 伤口愈合要求实验设计直接 检查伤口环境的要素并评估它们如何 影响细胞的生物学行为。他们的检测是设计的 从其他生物中剖析角质形成细胞运动的功能 细胞增殖等功能。他们最近的工作表明 清楚地表明结缔组织成分的类型 与基底角质形成细胞并置对诱导产生主要影响 迁移和停止迁移。除了细胞外基质 效应，角质形成细胞迁移可能受到选择性生长的影响 因素（如 EGF、TGFA 和 IL-1），但不受许多其他因素影响 可溶性因子（例如 NGF、IL-8、TGFb 等）。缺氧也是一大原因 影响角质形成细胞迁移的元素。在人体皮肤伤口中 使用经过处理的半渗透性封闭敷料进行处理 被证明可以促进上皮细胞再生和伤口愈合， 愈合皮肤伤口的微环境的特点是氧气非常低 张力和低 pH 值。根据体内观察，他们 最近的初步观察表明角质形成细胞表现出 缺氧条件下迁移增强。在这个提案中，他们希望 探索人类角质形成细胞迁移的细胞机制 结缔组织成分。此外，他们希望检查这些 常氧和低氧条件下的细胞机制 验证它们在微环境中的生物学重要性 类似于真正伤口愈合的环境。具体目标是 (i) 检查层粘连蛋白和层粘连蛋白亚型的作用（层粘连蛋白 5 = epiligrin， Kalinin、Nicein）对角质形成细胞运动的影响并确定是否缺氧 改变角质形成细胞的合成和基质粘附的沉积 分子，(ii) 确定片状伪足相关的作用 角质形成细胞迁移中的蛋白质（ezrin、moesin、radixin） 确定缺氧对这些表达的影响 板状伪足相关成分，(iii) 检查整合素受体 在常氧和缺氧条件下的活动和非活动角质形成细胞中 条件，以及（iv）检查金属蛋白酶的作用及其 角质形成细胞迁移过程中的相应抑制剂 确定低氧和常氧条件是否会改变它们的表达。