Design and generation of new absorption-enabling peptides for oral delivery of biologics

设计和生成用于口服生物制剂的新型吸收肽

• 批准号: 2088050
• 金额: --
• 依托单位: King's College London
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2018
• 资助国家: 英国
• 起止时间: 2018 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2088050
• 关键词: Design; generation; new; absorption; enabling

The project aligns with BBSRC's strategic research priority 3, 'Bioscience for Health' (Biotechnology for Health challenge) as it aims to develop basic bioscience underpinning the formulation and validation of biologics that benefit the maintenance and promotion of health. Building on applicants' prior work and benefiting from synergy, multidisciplinarity and Proxima's technologies, the project will develop a new generation of materials for oral delivery of biologics.Biologics have transformed therapeutics (7 out of 8 top selling drugs in 2014). Their administration is limited to injection due to negligible intestinal absorption. These are less accepted by patients (painful/potential side effects), and expensive to manufacture and administer. Several barriers limit systemic absorption of biologics, but the intestinal epithelium is the most formidable and challenging to overcome. Current approaches to improve oral biologics absorption typically employ 'absorption enhancers' that non-selectively disrupt and increase intestinal permeability, but safety concerns (eg. many surfactants) have hindered clinical translation. Therefore, there is an unmet need in safe and effective technologies for oral delivery of biologics.Key to safe and effective oral delivery of biologics are materials that 'smuggle' drugs selectively across the intestinal mucosa without disrupting this physiologically important barrier. These can be conjugated to the drug or drug delivery systems (e.g. nanoparticle). This project aims to develop novel transcytosis-enabling materials that promote oral absorption of biologics without disrupting the epithelium. These are peptide-based, designed taking inspiration from a natural macromolecular ligand that readily crosses the intestinal mucosa by transcytosis via its receptor, namely IgG and neonatal Fc receptor (FcRn). Preparation of transcytosis-enabling compounds will be informed by the receptor and ligand binding epitopes of IgG and FcRn.Vllasaliu previously demonstrated that FcRn shuttles IgG Fc-coated nanoparticles transepithelially. Proxima's discovery platforms will be used to prepare transcytosis-enabling peptide constructs. In Mozaic, prototype peptides are created from micellar nanoparticles bearing combinations of amino acids (AA) on surface. A screening library is constructed and after cell culture testing, most effective combination selected for peptide synthesis. AA choice is informed by sequences in IgG receptor-binding domains. In parallel, Almanac (algorithms derived from data of structural analyses of protein-protein interactions) will be used to infer the structure of ligand-binding peptides based on receptor binding domain sequence. Developing FcRn-binding ligands using two complementary approaches reduces the risk of failure.Project stagesYr 1: Student training in project relevant techniques and study of IgG-FcRn sequences Yr 1&2: Formulation of Mozaic screening libraries and peptides with a suitable fluorophore for quantitation. Purification (HPLC) and characterisation by MSYr 3&4: Testing compounds alone and conjugated to a model protein (albumin) for cell uptake and absorption across Caco-2 monolayers (intestinal model). Competition assays testing an FcRn receptor-mediated effect. Uptake mechanisms determined by siRNA inhibition of specific pathways and confocal microscopy (co-localisation studies)Yr 4: Testing most successful compounds' absorption ex vivo in excised rat intestine

该项目与BBSRC的战略研究重点3“生物科学促进健康”（生物技术促进健康挑战）保持一致，因为它旨在发展基础生物科学，以支持有利于维护和促进健康的生物制剂的配制和验证。基于申请人之前的工作，并受益于协同作用，多学科和Proxima的技术，该项目将开发新一代口服生物制剂材料。生物制剂已经改变了治疗方法（2014年8种最畅销药物中的7种）。由于肠道吸收可忽略不计，其给药仅限于注射。这些药物不太被患者接受（疼痛/潜在的副作用），并且生产和给药昂贵。有几个障碍限制了生物制剂的全身吸收，但肠上皮是最难克服和最具挑战性的。目前改善口服生物制剂吸收的方法通常采用非选择性破坏和增加肠道通透性的“吸收促进剂”，但安全性问题（例如，许多表面活性剂）阻碍了临床转化。生物制剂安全有效口服给药的关键是选择性地“走私”药物穿过肠粘膜而不破坏这一重要的生理屏障的材料。这些可以与药物或药物递送系统（例如纳米颗粒）缀合。该项目旨在开发新型转胞吞使能材料，促进生物制剂的口服吸收，而不破坏上皮。这些是基于肽的，其设计灵感来自天然大分子配体，该配体通过其受体（即IgG和新生儿Fc受体（FcRn））的转胞吞作用容易穿过肠粘膜。使能转胞吞作用的化合物的制备将通过IgG和FcRn的受体和配体结合表位来通知。Vllasaliu先前证明FcRn穿梭IgG Fc包被的纳米颗粒经上皮。Proxima的发现平台将用于制备转胞吞作用肽构建体。在Mozaic中，原型肽是由表面上带有氨基酸（AA）组合的胶束纳米颗粒产生的。构建筛选文库，并在细胞培养测试后，选择最有效的组合用于肽合成。AA选择由IgG受体结合结构域中的序列决定。同时，Almanac（源自蛋白质-蛋白质相互作用结构分析数据的算法）将用于基于受体结合结构域序列推断配体结合肽的结构。使用两种互补方法开发FcRn结合配体降低了失败的风险。项目阶段Yr 1：学生培训项目相关技术和IgG-FcRn序列的研究Yr 1&2：Mozaic筛选文库和具有合适荧光团的肽用于定量。通过MSYr 3&4进行的纯化（HPLC）和表征：测试单独的化合物和与模型蛋白（白蛋白）缀合的化合物的跨Caco-2单层（肠模型）的细胞摄取和吸收。测试FcRn受体介导的作用的竞争测定。通过siRNA抑制特定途径和共聚焦显微镜（共定位研究）确定的摄取机制第4年：在离体大鼠肠中测试最成功的化合物的离体吸收