CONTRACTION INHIBITION PRECEDING DERMAL REGENERATION

这项拟议的研究是对伤口收缩的体外研究。 某些特征良好的胶原-GAG(CG)基质的抑制作用。一个 这些高度多孔的CG矩阵中的一小类显著延迟了 生理性真皮的活体收缩和诱导再生 一种啮齿动物模型，其中的真皮不会自发再生。 有证据表明，抑制收缩对 再生。成纤维细胞填充的体外模型的建立 多孔CG矩阵将被用来仔细研究 受控的细胞外基质环境对成纤维细胞行为的影响。 细胞外基质受体(整合素)与成纤维细胞的关系 活动(迁移与收缩)和胶原结构(松散) 纤维与紧密堆积的胶原蛋白表面)将被建立。 整合素受体利用的变化由 收缩开始前后的免疫定位将是 由光学和电子显微镜测定。免疫电子显微镜 将用于将特定的整合素受体共同定位于肌动蛋白 收缩成纤维细胞的细胞骨架成分及其相互关系 受体在微丝重组和胶原蛋白中的应用 地形。这将检验多孔CG矩阵的假设 影响受体的利用和组织 成纤维细胞的细胞骨架元件从而控制细胞的活性 迁徙和收缩。成纤维细胞介导的效应 基于新合成的收缩和多孔CG矩阵结构 胶原纤维束组织的研究也将长期进行 添加抗坏血酸的培养物。成纤维细胞的程度 多孔CG矩阵的压缩与CG矩阵的结构 将独立地变化，以便研究它们在 胶原纤维束组织。这将允许确定 CG矩阵是否改变了新合成的基本组织 结缔组织与创面是否有机械应力收缩 是排列和紧凑胶原纤维束的主要因素 变成了疤痕组织。CG矩阵对受试者反应能力的影响 成纤维细胞能促进已知的生长因子增加胶原合成 也要有决心。这些都是基础研究，将阐明 CG基质抑制收缩的分子机制及 收缩和CG矩阵架构在组织中的作用 新形成的组织中有胶原纤维束。这些研究将 提高对细胞-基质相互作用影响的理解 正常伤口愈合事件和结缔组织再生。

The proposed research is an in vitro study of wound contraction inhibition by certain well-characterized collagen-GAG (CG) matrices. A small class of these highly porous CG matrices have significantly delayed in vivo contraction and induced regeneration of a physiologic dermis in a rodent model in which the dermis does not regenerate spontaneously. Evidence suggests that inhibition of contraction is necessary for regeneration. An in vitro model consisting of fibroblast-populated porous CG matrices will be used to study the effects of carefully controlled extracellular matrix environments upon fibroblast behavior. The relationship between ECM receptor utilization (integrins), fibroblast activity (migration vs. contraction), and collagen topography (loose fibrils vs. densely packed collagen surfaces) will be established. Changes in integrin receptor utilization as determined by immunolocalization before and after the onset of contraction will be determined by light and electron microscopy. Immunoelectron microscopy will be used to co-localize specific integrin receptors to actin cytoskeletal elements of contractile fibroblasts in order to correlate receptor utilization to microfilament reorganization and collagen topography. This will test the hypothesis that porous CG matrices influence the utilization of receptors and the organization of cytoskeletal elements of fibroblasts thus controlling activities of migration and contraction. The effects of fibroblast mediated contraction and porous CG matrix architecture upon newly synthesized collagen fibril bundle organization will also be studied in long-term cultures supplemented with ascorbic acid. The degree of fibroblast contraction of porous CG matrices and the architecture of CG matrices will be independently varied in order to study their separate roles in collagen fiber bundle organization. This will allow determination of whether CG matrix alters the basic organization of newly synthesized connective tissue and whether the mechanical stress of wound contraction is the primary factor in aligning and compacting collagen fiber bundles into scar tissue. The effect of CG matrix upon the responsiveness of fibroblasts to growth factors known to increase collagen synthesis will also be determined. These are basic studies which will elucidate the molecular mechanism by which CG matrices inhibit contraction and the roles of contraction and CG matrix architecture upon organization of collagen fiber bundles in newly formed tissue. These studies will improve the understanding of the effects of cell-matrix interactions in normal wound healing events and in connective tissue regeneration.