COLLAGEN METABOLISM IN WOUND REPAIR AND KELOID

本项目的长期目标是确定和分析 参与调节的细胞相互作用和分子机制 组织修复过程中的胶原代谢。为实现这一目标， 生物化学表征来源于正常人的成纤维细胞亚群 真皮、瘢痕和瘢痕疙瘩的胶原蛋白合成、胶原酶 表达以及TGF β受体数量和亲和力。这些研究测试 假设纤维化是选择成纤维细胞的结果， 能够产生增加量的胶原蛋白的亚群。在 此外，正在进行的研究将完成，以确定 在创伤早期观察到的产生胶原的单核细胞 修复.然后，这种特定的细胞群将从细胞中被消除。 伤口部位，以确定其在组织 修复.在其他研究中，胶原蛋白，纤连蛋白， 胶原酶和TGF β将在正常和生物学中定量。 损害大鼠伤口，以检查转录控制机制， 组织修复这些信息将与实际的 使用Western印迹分析定量这些蛋白质的表达， 伤口液和组织提取物以及免疫组织化学 本地化此外，将对胶原酶进行定量，以确定 胶原蛋白降解在胶原蛋白沉积的净量中的作用 伤口部位胶原酶mRNA的量将与 酶的活性，分析酶的调控机制。瘢痕疙瘩 将外植体置于无胸腺裸鼠上以研究胶原代谢 在体内使用氧-18标记技术。这将有助于研究 瘢痕疙瘩发病机制在体内的动力学，并提供初步数据， 最终在人体内进行研究。这种动物模型也应该被证明是有用的 用于评价治疗瘢痕疙瘩的药理学试剂。可能的作用 肥大细胞和肿瘤坏死因子（TN-F）在瘢痕疙瘩形成中的作用将 在无胸腺裸鼠模型以及细胞模型中检测 文化这些研究的最终结果将是更好地了解 调节正常伤口修复的分子机制，以及这些机制如何 在异常修复中调节事件被改变。

The long-term objective of this project is to define and analyze the cellular interactions and molecular mechanisms involved in the regulation of collagen metabolism during tissue repair. This objective will be met by biochemically characterizing fibroblast subpopulations derived from normal dermis, scar, and keloids with respect to collagen synthesis, collagenase expression and TGFbeta receptor number and affinities. These studies test the hypothesis that fibrosis is the result of a selection of fibroblast subpopulations capable of producing increased amounts of collagen. In addition, ongoing studies will be completed to identify the collagen-producing monocytes observed during the early phase of wound repair. This specific population of cells will then be eliminated from the wound site to determine its physiological significance during tissue repair. In other studies, the amount of mRNA for collagens, fibronectin, collagenase and TGFbeta will be quantitated in normal and biologically compromised rat wounds to examine transcriptional control mechanisms during tissue repair. This information will be correlated with the actual expression of these proteins as quantitated using Western blot analysis of wound fluid and tissue extracts as well as immunohistochemical localization. In addition, collagenase will be quantitated to determine the role of collagen degradation in the net amount of collagen deposited in a wound site. The amount of collagenase mRNA will then be correlated with enzyme activity to analyze the mechanism of enzyme regulation. Keloid explants will be placed onto athymic nude mice to study collagen metabolism in vivo using oxygen-18 labeling techniques. This will allow a study of the dynamics of keloid pathogenesis in vivo and provide initial data for eventual in vivo human studies. This animal model should also prove useful for evaluation of pharmacologic agents to treat keloids. The probable role of the mast cell and tumor necrosis factor (TN-F) in keloid formation will be examined both in the athymic nude mouse model as well as in cell culture. The net result of these studies will be a better understanding of the molecular mechanisms which regulate normal wound repair and how these regulatory events are altered in abnormal repair.