A novel approach for long term protein delivery

一种长期蛋白质输送的新方法

• 批准号: 7141503
• 负责人: You Han Bae
• 金额: $ 22.72万
• 依托单位: UNIVERSITY OF UTAH
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-08-01 至 2010-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7141503
• 关键词: SDS polyacrylamide gel electrophoresis; anions; biodegradable product; chemical kinetics; chemical synthesis; chromatography; conformation; copolymer; diabetes mellitus; disease /disorder model; drug delivery systems; histidine; insulin; ionic bond; laboratory rat; matrix assisted laser desorption ionization; microcapsule; nuclear magnetic resonance spectroscopy; polyethylene glycols; polymers; protein structure function; radioimmunoassay; ultraviolet spectrometry; water solution

DESCRIPTION (provided by applicant): Poly(lactide-co-glycolide) (PLGA) has been widely applied in microspheres (MS) as a protein delivery carrier. However, proteins undergo physical and chemical denaturation during the fabrication of PLGA MS and release in the body. In addition, such formulations often cause undesirable and unpredictable release profiles, characterized by a burst effect and incomplete release. This makes PLGA MS appraoch unsuccessful for most labile proteins. The results from our preliminary study are a clear pointer to the validity of the role played by PEG-polycation (poly(L-histidine)) as a pH-dependent 'reversible molecular shield' in 1) preserving protein structure and preventing aggregation at water/organic interface, 2) exerting a pH buffering (protein sponge effect) in PLGA MS, 3) enhancing protein's physical stability in solution and in MS, and 4) an overall better control over release of the proteins from the PLGA MS ('all-in-one' concept). Although our preliminary results demonstrate the feasibility, there are still a number of variables which can be altered to optimize or tailor this polymer design for specific proteins, such as insulin. This includes changing the size of polyHis and copolymerizing with other amino acids to alter charge spacing or polyHis conformation. The proposal goes well beyond therapeutic proteins in suggesting potential applications for enzymes and other applications. The long-term goal of this project is to preserve >90 % bioactivity of a model protein, insulin, when released from PLGA MS and to achieve pseudozero-order release kinetics for more than one month period in in vitro and in vivo tests. The research specific aims include 1) experimental verification of optimized PEG-polyHis (or PEG-modified polyHis)/insulin complex for maximum insulin stability in aqueous solutions, in PLGA MS and during release, 2) a better control over release profile and 3) in vivo performance tests combined with biocompatibility and the fate of the diblock copolymer.

描述（申请人提供）：聚丙交酯乙交酯（PLGA）作为蛋白质递送载体已广泛应用于微球（MS）中。然而，蛋白质在 PLGA MS 的制造和释放到体内的过程中会发生物理和化学变性。此外，此类制剂常常导致不期望的且不可预测的释放曲线，其特征在于突释效应和不完全释放。这使得 PLGA MS 方法无法成功检测大多数不稳定的蛋白质。我们的初步研究结果清楚地表明 PEG-聚阳离子（聚（L-组氨酸））作为 pH 依赖性“可逆分子盾”在 1) 保护蛋白质结构和防止在水中聚集所发挥的作用的有效性/有机界面，2) 在 PLGA MS 中发挥 pH 缓冲作用（蛋白质海绵效应），3) 增强蛋白质在溶液和 MS 中的物理稳定性，以及 4) 更好地全面控制蛋白质从 PLGA MS 的释放（“一体化”概念）。尽管我们的初步结果证明了可行性，但仍有许多变量可以改变，以优化或定制针对特定蛋白质（例如胰岛素）的聚合物设计。这包括改变多聚组氨酸的大小以及与其他氨基酸共聚以改变电荷间距或多聚组氨酸构象。该提案远远超出了治疗性蛋白质的范围，还提出了酶和其他应用的潜在应用。该项目的长期目标是在从 PLGA MS 释放时保留模型蛋白胰岛素的生物活性 >90%，并在体外和体内测试中实现超过 1 个月的伪零级释放动力学。该研究的具体目标包括 1) 优化 PEG-聚组氨酸（或 PEG 修饰的聚组氨酸）/胰岛素复合物的实验验证，以实现水溶液、PLGA MS 和释放过程中胰岛素的最大稳定性，2) 更好地控制释放曲线，以及 3)体内性能测试与生物相容性和二嵌段共聚物的命运相结合。