Recapitulation of the salivary gland niche ex vivo for stem cell-based therpies

项目摘要 唾液是保护口腔健康的重要防御机制。唾液腺功能减退 导致失控和严重的口腔疾病，严重影响生活质量。SGS 分化程度很高，一旦被治疗或破坏，几乎没有再生能力 疾病(如放射治疗或自身免疫性干燥综合征)。因此，中国的发展 保护或再生SGS的分泌功能的策略是成功的关键 这些病人的管理。细胞外基质(ECM)是独一无二的 在体内引导和维持细胞分化功能的微环境或“利基” 目前，干细胞再生疗法存在两个主要障碍：1)局限性 多能干细胞的可用性和2)选择性控制分化的困难 将多能干细胞转化为所需的细胞谱系。我们的研究小组开发了一种新型的ECM- 体外扩增多潜能骨髓间充质干细胞的细胞培养体系 骨髓和三维丝素支架(SFS)用于体外建立SG生态位。因此，我们 建议测试建立在自然3D上的唾液腺特异性ECM(SG-ECM)的假设 SFS，是一个能够引导MSC增殖和分化为功能性SG的仿生利基 祖细胞。在具体目标1中，我们将优化脚手架特性，以生产SG- 原代SG上皮细胞对SFS的ECM作用。在具体目标2中，我们将确定是否 最佳的SG-ECM包被的SFS可引导MSC分化为SG细胞系。在具体目标3中， 在特定目标2中产生的细胞的有效性将在脑血管损伤的活体模型中进行评估 由于受到辐射。 这一建议的新颖性包括：(1)测试我们的新型细胞培养技术，以获得足够的 人骨髓多能间充质干细胞修复或再生SG功能的数量；(2)检测 一种天然3D支架材料及其支持脑组织再生和组织的性能优化 工程学；(3)检测SG衍生的ECM涂层支架在引导MSC分化中的作用 以及(4)组建一个多学科团队进行研究 干细胞为基础的SG疗法。这项研究的成功可能会导致新的治疗策略 孤束核功能障碍的临床处理。

Project Summary Saliva is an important defense mechanism for protecting oral health. Salivary gland (SG) hypofunction results in uncontrolled and severe oral diseases that lead to severely compromised quality of life. SGs are highly differentiated and have little regenerative capacity once they are destroyed by therapy or disease (e.g. radiation therapy or autoimmune Sjögren’s syndrome). Therefore, the development of strategies for preserving or regenerating the secretory function of SGs is essential for successful management of these patients. The extracellular matrix (ECM) is a major component of the unique microenvironment or “niche” that directs and maintains the differentiated functions of cells in vivo Presently, there are two main obstacles to stem cell-based regenerative therapies: 1) the limited availability of multi-potent stem cells and 2) the difficulty of selectively controlling the differentiation multi-potent stem cells into the desired cell lineage. Our research group has developed a novel ECM- based cell culture system for expanding multipotent mesenchymal stem cells (MSCs) from bone marrow and 3D silk fibroin scaffolds (SFS) for establishing the SG niche ex vivo. Therefore, we propose to test the hypothesis that salivary gland specific ECM (SG-ECM), established on a natural 3D SFS, is a biomimetic niche capable of directing MSC proliferation and differentiation into functional SG progenitor cells. In Specific Aim 1, we will optimize scaffold characteristics for the production of SG- ECM on the SFS by primary SG epithelial cells. In Specific Aim 2, we will determine whether the optimal SG-ECM coated SFS directs MSC differentiation into the SG cell lineage. In Specific Aim 3, the efficacy of the cells, produced in Specific Aim 2, will be evaluated in an in vivo model of SG damage due to irradiation. The novelty of this proposal includes (1) testing our novel cell culture technology to obtain sufficient numbers of multipotent MSCs from human bone marrow to repair or regenerate SG function; (2) testing a natural 3D scaffold material and optimizing its properties for supporting SG regeneration and tissue engineering; (3) examining the role of SG-derived ECM coated scaffolds in directing MSC differentiation to the SG cell lineage and functional SG units, and (4) assembling a multidisciplinary team to study stem-cell based SG therapy. The success of this study may lead to new therapeutic strategies for clinical management of SG dysfunction.