MATRIX REGULATION OF GINGIVAL RE-EPITHELIZATION

口腔被膜的持续完整性要求伤者 牙龈重新上皮化。在此过程中，位于 伤口由新环境诱导附着、扩散、迁移和 最终通过伤口细胞外基质(ECM)侵入。 来自该实验室和其他实验室的大量数据表明， 一组细胞外基质受体，整合素，在调节 细胞与细胞外基质的相互作用。这项提议旨在调查 损伤后整合素受体的一个子集的假设 促进活化的角质形成细胞最初向外迁移 伤口基质。然后继续迁移，直到细胞联系到 相对伤口边缘，此时移动受到限制，以及第二个 整合素介导的一组信号限制运动和诱导形成 新的半桥粒和基底膜。重新--的过程 上皮化也可能受到创伤细胞因子的调节，如 作为转化生长因子-β，并要求角质形成细胞阐述特定的蛋白酶， 包括纤溶酶原激活物和金属蛋白酶。 拟议的研究将使用新分离的和新分离的 体外培养的人牙周角质形成细胞(HGK) 人牙龈上皮细胞和组织活检三个阶段的分析 创面愈合：STRATE的活化、迁移和重塑 附着体，如半桥粒。整合素受体的激活 在HGK后立即使用功能和 HGK与配体相互作用的生化分析 伤口床。整合素的合成、组装和表达的变化 时间之后还将进行脉冲追逐标记和流式细胞术 新鲜分离培养的基础HGK。蛋白质的配基特异性 将通过细胞附着、亲和力来分析特定的HGK整合素 层析和受体结合分析。有没有可能 某些整合素，特别是α3beta1和alpha6beta4， 在促进和阻止移民方面的重要性将被研究。也是 有待研究的是HGK调控细胞迁移的可能性 含有外植素/加里宁的ECM地毯的沉积； HGK激活过程中和激活后的特定蛋白水解酶以及可能的 创伤细胞因子转化生长因子-β对整合素谱的调节作用 迁移反应、细胞外基质沉积和蛋白酶表达。 这些研究将增加对动态过程的理解。 稳定的上皮附着的激活、迁移和重组 发生在牙龈伤口愈合过程中。它们与 牙周炎进展过程中结合上皮的迁移 以及牙周后交界上皮的愈合 外科治疗。

Continued integrity of the oral integument requires that the wounded gingiva re-epithelialize. In this process, cells at the margin of a wound are induced by a new environment to attach, spread, migrate, and eventually invade through the wound extracellular matrix (ECM). Substantial data from this and other laboratories indicate that the major group of ECM receptors, the integrins, are critical in mediating interactions of cells with the ECM. This proposal seeks to investigate the hypothesis that after injury one subset of integrin receptors promotes the initial out-migration of activated keratinocytes on the wound matrix. Migration then proceeds until the cells contact the opposing wound margin, at which time movement is restricted, and a second set of integrin-mediated signals restricts movement and induces formation of new hemidesmosomes and basement membrane. The process of re- epithelization is also likely to be modulated by wound cytokines, such as TGF-beta, and requires keratinocytes to elaborate specific proteases, including plasminogen activators and metalloproteinases. The proposed studies will use model systems of freshly dissociated and cultured human gingival keratinocytes (HGK), explants of human gingival epithelium, and tissue biopsies of human gingiva to analyze three stages of wound healing: activation, migration and reformation of stable attachment such as hemidesmosomes. The activation of integrin receptors immediately after HGK dissociation will be assessed using functional and biochemical assays to characterize HGK interaction with ligands in the wound bed. Changes in integrin synthesis, assembly, and expression over time will also be followed by pulse-chase labeling and flow cytometry of freshly dissociated and cultured basal HGK. The ligand specificity of specific HGK integrins will be analyzed by cell attachment, affinity chromatography, and receptor-binding assays. The possibility that certain integrins, particularly alpha3beta1 and alpha6beta4, are important in promoting and then halting migration will be examined. Also to be studied are the possibility that cell migration is regulated by HGK deposition of an ECM carpet containing epiligrin/kalinin; the expression of specific proteases during and after HGK activation and the possible modulating effect of the wound cytokine TGF-beta on integrin profiles, migratory response, ECM deposition, and protease expression. These studies will increase understanding of the dynamic processes of activation, migration and reorganization of stable epithelial attachments that occur in gingival wound healing. They are highly relevant to the migration of junctional epithelium in the progression of periodontitis, as well as healing of the junctional epithelium after periodontal surgical therapy.