CONTRACTION INHIBITION PRECEDING DERMAL REGENERATION

真皮再生前的收缩抑制

• 批准号: 3309164
• 负责人: IOANNIS V YANNAS
• 金额: $ 14.7万
• 依托单位: MASSACHUSETTS INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-08-01 至 1996-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3309164
• 关键词: actins; artificial skin; ascorbate; biological models; chondroitin sulfates; collagen; copolymer; cytoskeleton; extracellular matrix; fibroblasts; immunoelectron microscopy; integrins; regeneration; scars; tissue /cell culture; wound healing

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.

拟议的研究是对伤口收缩的体外研究 通过某些特征良好的胶原蛋白-GAG（CG）矩阵的抑制作用。 一个 这些高度多孔CG矩阵的小类已显着延迟 体内收缩和诱导生理真皮的再生 真皮不会自发再生的啮齿动物模型。 有证据表明，抑制收缩是必要的 再生。 由成纤维细胞填充的体外模型 多孔CG矩阵将用于研究仔细的效果 成纤维细胞行为后，受控的细胞外基质环境。 ECM受体利用率（整合素），成纤维细胞之间的关系 活动（迁移与收缩）和胶原蛋白地形（松散 将建立原纤维与密集的胶原蛋白表面）。 整联蛋白受体利用的变化，确定 收缩开始之前和之后的免疫定位将是 由光和电子显微镜确定。 免疫电子显微镜 将用于将特定整合素受体共定位到肌动蛋白 收缩成纤维细胞的细胞骨架元素，以便相关 受体利用来重组微丝和胶原蛋白 地形。 这将测试多孔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素，从而控制活性 迁移和收缩。 成纤维细胞介导的作用 新合成的收缩和多孔CG矩阵架构 胶原纤维束组织也将长期研究 补充抗坏血酸的培养物。 成纤维细胞的程度 多孔CG矩阵的收缩和CG矩阵的结构 为了研究其在 胶原纤维束组织。 这将允许确定 CG矩阵是否改变新合成的基本组织 结缔组织以及伤口收缩的机械应力是否 是对齐和压实胶原蛋白纤维束的主要因素 进入疤痕组织。 CG矩阵对响应性的影响 成纤维细胞与已知增加胶原蛋白合成的生长因子将 也可以确定。 这些是基本研究，可以阐明 CG矩阵抑制收缩和的分子机制 收缩和CG基质体系结构的作用 新形成的组织中的胶原纤维束。 这些研究会 提高对细胞基质相互作用的影响的理解 正常伤口愈合事件和结缔组织再生。