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.

受资助的父奖项或项目摘要。 当肾脏失去清除血液中毒素的能力时，透析是主要的治疗方法。然而， 透析不能复制健康肾脏的所有功能，因此，晚期慢性肾功能衰竭患者 接受透析的肾病(CKD)和终末期肾病(ESKD)的发病率继续居高不下 残留症状、心血管并发症和死亡率。人们越来越认识到 肠道微生物代谢的副产物，如蛋白结合尿毒症毒素(PBUT)吲哚硫酸盐和 对甲酚硫酸盐没有被有效去除，因为它们与血浆白蛋白紧密结合并留在 透析膜的血侧。肠道来源的PBUT的血浆浓度一再与 慢性肾脏病(CKD)患者的心血管发病率、认知功能下降和死亡率 终末期肾病(ESKD)。然而，多次尝试修改肾脏中的肠道微生物组 使用前生物制剂和益生菌的失败到目前为止还没有显示出显著的临床益处。 为了回应这一关键的未得到满足的需求，我们提出了一种完全不同的(高风险高回报)方法 基于生物工程原理和土木工程与环境的尿毒症毒性预防 工程战略，已在药物输送和废水处理方面取得了成功。我们的 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，这种颗粒可以被摄取 就像泡泡茶一样。水凝胶泡泡不会试图改变下面的微生物群，而是会 为他们的货物提供保护环境，使其以结肠为目标(主要形成和吸收部位 吲哚和对甲酚)，并将允许引入的细菌在治疗后离开消化系统，因此 避免了对人类微生物群落的干扰。 此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 一种新的无针技术，最终可以改善晚期CKD患者的健康状况 ESKD通过减少尿毒症毒性。我们的战略是将微生物学、生物反应器技术、 数学模型、尿毒症毒性、肠道功能和聚合物化学以防止 而不是试图将它们从血液中消除。我们的方法将利用 聚合物和水凝胶工程，以量身定做凝胶珠。凝胶中将含有固定化细菌， 将吲哚和对甲酚降解为无毒、有益或益生菌成分。这些凝胶的功能就像 对酸性胃中细菌的保护屏障，但将允许吲哚和对甲酚扩散到 微珠内部一旦达到pH中性的小肠和大肠，从而解锁最大的活性 生物去除PBUT。动力学数据将用于运行数学模型来预测细菌分布 在珠子中引导生物反应器实验。生物反应器将模拟通过肠道的旅程，并将 反映胃、小肠和大肠的状况(如pH值、氧气、营养物质)和转运时间。 我们提出了以下具体目标： 具体目标1：从环境来源丰富微生物群落或纯培养物 能够在有氧和厌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， 包裹尿毒症毒素降解微生物，并保持结构和功能的完整性以供传递 通过肠道，同时保留其货物的功能。 具体目标3：在放大的肠状柱状生物反应器中实现尿毒症毒素的体外降解，以告知 患者特定的每日泡茶剂量和配方。