Therapeutic bubble tea: Preventing the formation of uremic toxins with hydrogel immobilized microbes

治疗性珍珠奶茶：利用水凝胶固定微生物预防尿毒症毒素的形成

• 批准号: 10631801
• 负责人: Mari-Karoliina Winkler
• 金额: $ 0.74万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10631801
• 关键词: Aerobic; Aftercare; Amino Acids; Anaerobic Bacteria; Award; Bacteria; Binding; Binding Proteins; Biological; Biological Assay; Biomedical Engineering; Bioreactors; Blood; Blood Circulation; Cardiovascular system; Chemistry; Chronic Kidney Failure; Clinical; Colon; Communities; Cresol; Data; Dialysis procedure; Diffusion; Dose; Drug Delivery Systems; End stage renal failure; Engineering; Environment; Environmental Engineering technology; Excision; Formulation; Funding; Gastrointestinal tract structure; Gel; Goals; Human Microbiome; Hydrogels; Immobilization; Impaired cognition; In Vitro; Indican; Indoles; Ingestion; Intestines; Kidney; Kidney Failure; Kinetics; Large Intestine; Liver; Membrane; Metabolism; Microbe; Microbiology; Morbidity - disease rate; Needles; Nutrient; Oxygen; Parents; Patients; Performance; Personal Satisfaction; Plasma; Plasma Albumin; Polymer Chemistry; Polymers; Probiotics; Residual state; Running; Science; Side; Site; Small Intestines; Source; Stomach; Sulfate; Tea; Technology; Testing; Therapeutic; Time; Toxic effect; Toxin; absorption; base; design; experience; experimental study; gastrointestinal system; gut microbiome; high reward; high risk; improved; innovation; mathematical model; microbial; microbiome; microorganism; microorganism culture; mortality; novel; particle; preservation; prevent; protein degradation; response; scale up; solute; success; symptomatology; tool

Abstract of the funded parent award or project. Dialysis is the leading therapy when kidneys lose their capacity to remove toxins from the blood. However, dialysis cannot replicate all the functions of healthy kidneys and as a result, patients with advanced chronic kidney disease (CKD) and end-stage kidney disease (ESKD) receiving dialysis continue to experience high rates of residual symptomatology, cardiovascular complications, and mortality. It is increasingly recognized that byproducts of gut microbial metabolism, such as the protein-bound uremic toxins (PBUTs) indoxyl sulfate and para-cresol sulfate, are not effectively removed because they bind tightly to plasma albumin and remain on the blood side of dialysis membranes. The plasma concentrations of gut derived PBUTs has repeatedly been related to cardiovascular morbidity, cognitive decline, and mortality in patients with chronic kidney disease (CKD) and end stage renal disease (ESKD). However, multiple attempts to modify the intestinal microbiome in kidney failure with the use of pre- and pro-biotics have not demonstrated significant clinical benefit to date. In response to this critical unmet need, we propose a radically different (high risk high reward) approach to preventing uremic toxicity from PBUTs based on bioengineering principles and civil and environmental engineering strategies, which have had demonstrated success in drug delivery and wastewater treatment. Our innovation targets the degradation of PBUT precursors (indole and p-cresol) in the gut to prevent sulfonation in the liver to their toxic forms by using bacteria immobilized in hydrogel particles, which can be ingested similar to a bubble tea. Rather than attempting to alter the underlying microbiome, the hydrogel bubbles will provide a protective environment for their cargo to target the colon (primary site of formation and absorption of indole and p-cresol) and will allow the introduced bacteria to exit the digestive system after treatment, hence avoiding a disturbance of the human microbiome. The overarching goal of this application is to leverage these field-leading engineering tools, in order to develop a novel ‘needle free’ technology that ultimately can improve the wellbeing of patients with advanced CKD and ESKD by reducing uremic toxicity. Our strategy is to combine expertise in microbiology, bioreactor technology, mathematical modelling, uremic toxicity, intestinal function, and polymer chemistry in order to prevent formation of PBUTs, rather than trying to eliminate them from the bloodstream. Our approach will utilize polymer and hydrogel engineering to tailor gel beads. The gels will contain immobilized bacteria that will degrade indole and p-cresol to non-toxic, beneficial or probiotic components. The gels will function as protective barrier for the bacteria in the acidic stomach but will allow diffusion of indole and p-cresol into the bead interior once they reach the pH-neutral small and large intestine hence unlocking maximal activity for biological PBUT removal. Kinetic data will be used to run mathematical models to predict bacterial distribution in the beads to direct bioreactor experiments. The bioreactors will simulate the trip through the gut and will mirror the conditions (such as pH, oxygen, nutrients) and transit times of the stomach, small and large intestine. We propose the following specific aims: Specific Aim 1: Enrich a community or pure cultures of microorganisms from environmental sources which are capable of converting indole and p-cresol both aerobically and anaerobically, and to describe their kinetics and identity, and determine intermediate products. Specific Aim 2: Utilize polymer science and hydrogel engineering to design tailored hydrogel beads which enclose uremic toxin degrading microorganisms, and retain structural and functional integrity for passage through the gut, while preserving the functionality of their cargo. Specific Aim 3: Achieve in vitro uremic toxin degradation in a scaled-up gut-like column bioreactor, to inform a patient specific daily bubble tea dose and formulation.

受资助的家长奖项或项目的摘要。 当肾脏失去从血液中清除毒素的能力时，透析是主要的治疗方法。 透析无法复制健康肾脏的所有功能，因此，晚期慢性肾病患者 接受透析的肾脏疾病（CKD）和终末期肾脏疾病（ESKD）的发病率仍然很高 人们越来越认识到，残余症状、心血管并发症和死亡率。 肠道微生物代谢的副产物，例如蛋白质结合尿毒症毒素 (PBUT)、硫酸吲哚酚和 对甲酚硫酸盐不能有效去除，因为它们与血浆白蛋白紧密结合并保留在 肠道来源的 PBUT 的血浆浓度反复相关。 慢性肾病 (CKD) 患者的心血管发病率、认知能力下降和死亡率 然而，多种尝试改变肾脏肠道微生物组。 迄今为止，使用益生菌和益生菌的失败尚未显示出显着的临床益处。 为了应对这一未满足的关键需求，我们提出了一种截然不同的（高风险高回报）方法 基于生物工程原理和土木与环境预防PBUT的尿毒症毒性 工程策略，已在药物输送和废水处理方面取得了成功。 创新的目标是在肠道中降解 PBUT 前体（吲哚和对甲酚），以防止磺化 通过使用固定在水凝胶颗粒中的细菌在肝脏中转化为有毒形式，这些细菌可以被摄入 与珍珠奶茶类似，水凝胶气泡不会试图改变潜在的微生物群。 为其货物靶向结肠（形成和吸收的主要部位）提供保护环境 吲哚和对甲酚），并且将允许引入的细菌在处理后离开消化系统，因此 避免人类微生物群受到干扰。 该应用程序的总体目标是利用这些领域领先的工程工具，以便开发 一种新颖的“无针”技术最终可以改善晚期 CKD 患者的健康状况 我们的策略是结合微生物学、生物反应器技术、 数学模型、尿毒症毒性、肠道功能和高分子化学，以预防 我们的方法将利用 PBUT 的形成，而不是试图将它们从血液中消除。 聚合物和水凝胶工程来定制凝胶珠，凝胶将含有固定的细菌。 将吲哚和对甲酚降解为无毒、有益或益生菌成分。 酸性胃中细菌的保护屏障，但会允许吲哚和对甲酚扩散到胃中 一旦它们到达 pH 中性的小肠和大肠，珠子内部就会发生变化，从而释放最大活性 生物 PBUT 去除将用于运行数学模型来预测细菌分布。 生物反应器将模拟通过肠道的行程，并会指导生物反应器实验。 反映胃、小肠和大肠的状况（例如 pH、氧气、营养物质）和传输时间。 我们提出以下具体目标： 具体目标 1：从环境来源中丰富微生物群落或纯培养物， 能够在有氧和无氧条件下转化吲哚和对甲酚，并描述它们的动力学 和身份，并确定中间产品。 具体目标 2：利用聚合物科学和水凝胶工程设计定制的水凝胶珠， 封闭尿毒症毒素降解微生物，并保留结构和功能完整性以供传代 通过肠道，同时保留货物的功能。 具体目标 3：在放大的类肠柱生物反应器中实现体外尿毒症毒素降解，以告知 患者每日特定的泡茶剂量和配方。