MATRIX REGULATION OF GINGIVAL RE-EPITHELIZATION

牙龈再上皮化的基质调节

• 批准号: 6238501
• 负责人: RANDALL H KRAMER
• 金额: $ 26.9万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-12-01 至 1999-10-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6238501
• 关键词: affinity chromatography; basement membrane; biopsy; cell cell interaction; cell migration; epithelium; extracellular matrix; flow cytometry; gingiva; human tissue; integrins; intercellular connection; keratinocyte; ligands; oral mucosa; plasminogen activator; receptor binding; tissue /cell culture; transforming growth factors; wound healing

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.

口腔外皮的持续完整性要求伤员 牙龈重新上皮化。 在此过程中，边缘的细胞 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，主要 ECM 受体组（整合素）在介导 细胞与 ECM 的相互作用。 该提案旨在调查 假设受伤后整合素受体的一个子集 促进活化的角质形成细胞最初向外迁移 伤口基质。 然后迁移继续进行，直到细胞接触 相反的伤口边缘，此时运动受到限制，并且第二个 一组整合素介导的信号限制运动并诱导形成 新的半桥粒和基底膜。 重新的过程 上皮化也可能受到伤口细胞因子的调节，例如 作为 TGF-β，并且需要角质形成细胞来合成特定的蛋白酶， 包括纤溶酶原激活剂和金属蛋白酶。 拟议的研究将使用新分离的模型系统 培养的人牙龈角化细胞（HGK），人牙龈外植体 上皮细胞和人类牙龈组织活检来分析三个阶段 伤口愈合：稳定的激活、迁移和重建 附着物，例如半桥粒。 整合素受体的激活 HGK 解离后立即使用功能和 生化测定来表征 HGK 与配体的相互作用 伤口床。 整合素合成、组装和表达的变化 时间之后还将进行脉冲追踪标记和流式细胞术 新鲜解离和培养的基础 HGK。 配体特异性 特定的 HGK 整合素将通过细胞附着、亲和力进行分析 色谱法和受体结合测定。 的可能性是 某些整合素，特别是 α3β1 和 α6β4， 将审查对促进和停止移民的重要性。 还 待研究细胞迁移是否受HGK调节的可能性 含有 Epiligrin/kalinin 的 ECM 地毯沉积；表达式 HGK 激活期间和之后特定蛋白酶的变化以及可能的 伤口细胞因子 TGF-β 对整合素谱的调节作用， 迁移反应、ECM 沉积和蛋白酶表达。 这些研究将增加对动态过程的理解 稳定上皮附着的激活、迁移和重组 牙龈伤口愈合过程中发生的情况。 它们与以下内容高度相关 牙周炎进展过程中交界上皮的迁移， 以及牙周病治疗后连接上皮的愈合 手术治疗。