A stem cell activated cryogel bioscaffold that restores islet bioenergetics while providing oxygen and nutrients at extravascular sites of transplantation

干细胞激活的冷冻凝胶生物支架可恢复胰岛生物能，同时在血管外移植部位提供氧气和营养物质

• 批准号: 10445136
• 负责人: Avnesh Sinh Thakor
• 金额: $ 56.49万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-04-01 至 2027-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10445136
• 关键词: 3-Dimensional; Address; Alanine; Amino Acids; Anastomosis - action; Animal Model; Animals; Anti-Inflammatory Agents; Bioenergetics; Blood; Blood Vessels; Bone Marrow; C57BL/6 Mouse; Cells; Clinical Trials; Collagen; Data; Diffusion; Encapsulated; Ensure; Essential Amino Acids; Exhibits; Fatty acid glycerol esters; Fibrosis; Foreign-Body Reaction; Future; Glutamine; Guidelines; Health; Human; Hypoxia; Inflammatory; Inflammatory Response; Insulin; Islets of Langerhans Transplantation; Liver; Location; Mediating; Mesenchymal; Mesenchymal Stem Cells; Mitochondria; Mus; Nanotubes; Nutrient; Omentum; Operative Surgical Procedures; Oxygen; Pancreas; Portal vein structure; Process; Reaction; Secure; Seeds; Silicon Dioxide; Site; Source; Streptozocin; Stress; Techniques; Technology; Testing; Therapeutic; Time; Transplantation; Vascular blood supply; Work; base; beta cell replacement; bioscaffold; cell replacement therapy; clinically translatable; controlled release; cryogel; cytokine; diabetic; diabetic patient; exhaustion; extracellular vesicles; glycemic control; immunoregulation; implantation; inflammatory milieu; innovation; islet; islet stem cells; mouse model; nanoparticle; novel; paracrine; progenitor; response; stem cells; subcutaneous

PROJECT SUMMARY Islet transplantation is a β-cell replacement therapy used to treat diabetic patients who lack the ability to secrete insulin. The conventional site for islet transplantation is the liver, however, this is far from optimal given that islets are subjected to hypoxia, toxic metabolites from the liver, a pro-inflammatory environment and an instant blood- mediated inflammatory reaction (IBMIR); together, this results in up to 60-70% of islets being immediately lost following transplantation. Furthermore, given that islet transplantation does not require the creation of a surgical vascular anastomosis, islets therefore need to build and secure a dedicated blood supply, which takes at least 3 weeks. In the interim, islets have to survive by relying on the diffusion of oxygen and nutrients (such as essential amino acids like glutamine and alanine) from the microenvironment of the transplantation site, which results in them enduring significant stress and bioenergetic depletion. Accordingly, we have identified several critical problems in the transplantation process which we have addressed with our innovative and clinically translatable solution that will maintain islet health and survival, during, and following, their transplantation. Recently, we developed and validated a novel collagen based cryogel 3D matrix that incorporates an oxygen generator to address the problem of insufficient oxygen which causes islet hypoxia. In Aim 1, we will functionalize this bioscaffold platform with a nutrient generator in the form of a mesoporous silica nanoparticle that releases amino acids. The release of both oxygen and amino acids to islets using these technologies will be modulated to ensure it is continuous over 3-weeks. Given isolated islets are stressed and exhibit exhaustion, which is further exacerbated following their transplantation, in Aim 2 we will aim to re-energize islets and restore their bioenergetic potential immediately after isolation using bone marrow derived mesenchymal cells (BM-MSCs); these cells can transfer their healthy mitochondria to islets via tunneling nanotubes (TNTs) and this can be potentiated when BM-MSCs are in close proximity to islets – hence, we will activate our bioscaffold platform by pre-seeding it with BM-MSCs. In Aim 3, we will then test the ability of our optimized “active” bioscaffold to restore glycemic control in diabetic animal models at 2 extra-vascular sites of transplantation (i.e. the omentum and the subcutaneous space) given this will mitigate the IBMIR normally encountered by islets following their delivery into the liver via the portal vein. At each of these sites, we will examine whether our active bioscaffold elicits an inflammatory response and foreign body reaction in the short term, and fibrosis/encapsulation in the long term; we expect these responses to be minimal given our bioscaffolds are made from collagen and they contain BM- MSCs that have potent anti-inflammatory, immunomodulatory and anti-fibrotic effects via their paracrine ability to release cytokines and extracellular vesicles. This data will pave the way for future clinical trials with our novel platform which can be scaled and produced conforming to GMP guidelines.

项目概要 胰岛移植是一种β细胞替代疗法，用于治疗缺乏分泌能力的糖尿病患者 胰岛素。胰岛移植的传统部位是肝脏，然而，考虑到胰岛移植，这远非最佳。 受到缺氧、肝脏有毒代谢物、促炎环境和即时血液- 介导的炎症反应（IBMIR）；总之，这会导致高达 60-70% 的胰岛立即丢失 移植后。此外，鉴于胰岛移植不需要进行手术 因此，在血管吻合术中，胰岛需要建立并确保专用的血液供应，这至少需要 3周。在此期间，胰岛必须依靠氧气和营养物质（例如必需的 来自移植部位微环境的氨基酸（如谷氨酰胺和丙氨酸），从而导致 他们承受着巨大的压力和生物能量的消耗。因此，我们确定了几个关键的 我们通过创新和可临床转化的技术解决了移植过程中的问题 解决方案将在移植期间和移植后维持胰岛的健康和存活。最近，我们 开发并验证了一种基于胶原蛋白的新型冷冻凝胶 3D 基质，该基质结合了氧气发生器 解决氧气不足导致胰岛缺氧的问题。在目标 1 中，我们将对其进行功能化 具有营养生成器的生物支架平台，该营养生成器采用介孔二氧化硅纳米颗粒形式，可释放氨基 酸。使用这些技术向胰岛释放氧气和氨基酸将被调节，以确保 连续3周以上。鉴于孤立的小岛受到压力并表现出疲惫，这进一步 移植后恶化，在目标 2 中，我们的目标是为胰岛重新注入活力并恢复其功能 使用骨髓来源的间充质细胞 (BM-MSC) 分离后立即具有生物能潜力； 这些细胞可以通过隧道纳米管（TNT）将健康的线粒体转移到胰岛，这可以 当 BM-MSC 靠近胰岛时会增强 - 因此，我们将通过以下方式激活我们的生物支架平台 预先接种 BM-MSC。在目标 3 中，我们将测试优化的“活性”生物支架恢复的能力 糖尿病动物模型中 2 个血管外移植部位（即大网膜和网膜）的血糖控制 皮下空间），因为这将减轻胰岛在分娩后通常遇到的 IBMIR 经门静脉进入肝脏。在每个站点，我们将检查我们的活性生物支架是否引起 短期为炎症反应和异物反应，长期为纤维化/包膜； 鉴于我们的生物支架是由胶原蛋白制成的，并且它们含有 BM-，我们预计这些反应是最小的 间充质干细胞通过其旁分泌能力具有有效的抗炎、免疫调节和抗纤维化作用 释放细胞因子和细胞外囊泡。这些数据将为我们的新药未来的临床试验铺平道路 可以按照 GMP 指南进行扩展和生产的平台。