Extended preservation of human livers: a nature inspired, high subzero controlled, limited freezing approach

人类肝脏的长期保存：一种受自然启发、高度零下控制、有限冷冻的方法

• 批准号: 9910008
• 负责人: YOED RABIN
• 金额: $ 29.97万
• 依托单位: SYLVATICA BIOTECH, INC.
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-13 至 2022-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9910008
• 关键词: Achievement; Acute Liver Failure; Affect; Animals; Area; Arizona; Back; Biological Assay; Biomedical Engineering; Biomedical Research; Businesses; Cells; Clinical; Cryopreservation; Custom; Data; Devices; Dialysis procedure; Economics; Emergency Situation; Equilibrium; Equipment and supply inventories; Evaluation; Freezing; Future; Goals; Graft Rejection; Growth; Heart failure; Helicopter; Hepatocyte; Hour; Human; Ice; Immune Tolerance; Immunologics; In Vitro; Injury; Kidney; Kidney Failure; Kidney Transplantation; Learning; Length; Letters; Life; Liver; Liver Failure; Lobe; Longevity; Modeling; Nature; Operative Surgical Procedures; Organ; Organ Donations; Organ Preservation; Organ Procurements; Organ Transplantation; Outcome; Patients; Perfusion; Phase; Procedures; Protocols documentation; Quality of life; Rattus; Recovery; Resort; Resuscitation; Savings; Schedule; Slice; Stretching; System; Technology; Temperature; Thermodynamics; Time; Tissue Engineering; Tissues; Translating; Transplant Surgeon; Transplantation; Universities; Validation; Waiting Lists; Whole Blood; Work; animation; base; biomaterial compatibility; combinatorial; cost; design; experience; flexibility; high throughput screening; human model; improved; laboratory equipment; liver preservation; liver transplantation; metabolic depression; mortality; novel strategies; preconditioning; preservation; prototype; repaired; stress tolerance; success; transplant model; trauma care; ventricular assist device

ABSTRACT 1 in 5 liver waitlist patients do not receive a new liver in time, while many more patients are never listed but could benefit from liver replacement. While “bridge-to-transplant” technologies (ventricular assist devices and dialysis) have transformed the outlook for heart failure and kidney failure, no such treatment exists for patients with liver failure. Current liver sharing limits (approx. 500 miles) are based on limited preservation durations (6-10 hours). By extending preservation to just a few days we can enable nationwide (theoretically global) donor-recipient matching, allowing many livers that go untransplanted today (e.g. subsets of extended criteria donor livers that have been shown to offer substantial survival benefits) to be offered to the patients who most need them. Transplant surgeons have expressed excitement about this possibility, and it is thought that this achievement would have a profound impact on liver waitlist mortality. Among other benefits, this can also increase graft lifespan and reduce immunological rejection, eliminate the need for costly jet and helicopter transport, transform the practice of liver transplantation from emergency surgery to a flexibly scheduled procedure, and mitigate the severe disparities in liver transplantation. It will also allow immune tolerance induction protocols that have now achieved success in living donation to be adapted to the deceased donor context. To meet these needs, we will develop a comprehensive system for banking human livers for transplantation for periods of 5-7 days with a stretch goal of 10+ days or longer. We have created an integrated two-pronged approach to develop new stasis cocktails optimized for the critical phases of liver preservation: preconditioning and protection (prior to storage), preservation (during storage) and revival- resuscitation-repair (after storage). In parallel, we are creating devices for advanced perfusion, storage, and organ assessment before transplant decision. Our approach adapts the best strategies of freeze-tolerant and hibernating species, augmenting them with recent scientific and bioengineering advances. Importantly, we do not seek to solve all the problems of classical cryopreservation, but rather to be the first to develop preservation in thermodynamic equilibrium at high subzero (HSZ) temperatures (-10°C to -30°C), combined with programmed metabolic depression and enhanced stress tolerance. Feasibility of this approach has already been demonstrated; we have banked rat livers for 5 days at HSZ temperatures, and successfully preserved the first whole human liver lobe at -15°C. For this fast-track proposal, the Phase 1 goal will be to further refine our protocols and validate our initial unprecedented storage duration by banking rat livers for 5-7 days and using comprehensive post-preservation normothermic machine perfusion with functional assessment. We will also scale to whole human liver lobes, with subsequent hepatocyte isolation. Phase 2 will focus on optimizing key parameters that affect preservation outcomes in rat and human livers. Our goal is 6-10+ days of storage via (i) optimal modulation of ice growth, (ii) nature-inspired de-toxify/reenergize perfusion phase and (iii) precise control of thermodynamics using a prototype Bio-Thermodulator device.

摘要 五分之一的肝脏等待名单患者没有及时获得新的肝脏，而更多的患者从未被列入名单，但可能会 受益于肝脏替代。虽然“移植桥”技术（心室辅助装置和透析） 已经改变了心力衰竭和肾衰竭的前景，但对于肝衰竭患者还没有这种治疗方法。 失败目前的肝脏共享限制（大约。500英里）是基于有限的保存时间（6-10小时）。 通过将保存时间延长到几天，我们可以使全国范围内（理论上是全球性的）的捐赠者-接受者 匹配，允许许多今天未移植的肝脏（例如， 已被证明提供实质性的生存益处）提供给最需要它们的患者。 移植外科医生对这一可能性表示兴奋，人们认为这一成就 会对肝脏等待名单的死亡率产生深远的影响。在其他好处中，这也可以增加嫁接 寿命和减少免疫排斥，消除了昂贵的喷气式飞机和直升机运输的需要， 肝移植的实践从急诊手术到灵活安排的程序，并减轻 肝脏移植的严重差异。它还将允许免疫耐受诱导方案， 在活体捐赠方面取得了成功，以适应已故捐赠者的情况。为了满足这些需求，我们 将开发一个全面的系统，用于储存5-7年的人类肝脏移植。 以10天以上或更长时间的拉伸目标为目标。我们采取了双管齐下的综合办法， 开发新的停滞鸡尾酒，优化肝脏保存的关键阶段：预处理和保护 （储存前）、保存（储存期间）和复苏-复苏-修复（储存后）。同时，我们 正在制造先进的灌注、储存和器官评估设备，然后再决定移植。我们 方法采用了最佳的策略，抗冻和冬眠的物种，增加他们与最近的 科学和生物工程的进步。重要的是，我们并不寻求解决所有的问题，经典 冷冻保存，而是要成为第一个在零下高温下发展热力学平衡保存的人 (HSZ)温度（-10 ° C至-30 ° C），结合程序性代谢抑制和增强的压力 宽容这种方法的可行性已经得到了证实;我们已经将大鼠肝脏储存了5天 在HSZ温度下，并成功地在-15 ° C下保存了第一个完整的人类肝叶。为了这个快速通道 根据该提案，第1阶段的目标将是进一步完善我们的协议，并验证我们最初前所未有的存储 大鼠肝脏保存5-7天，采用综合性保存后常温机保存 灌注与功能评估。我们还将扩展到整个人类肝叶，随后的肝细胞 隔离第2阶段将重点优化影响大鼠和人类肝脏保存结果的关键参数。 我们的目标是6-10天以上的存储，通过（i）最佳的调节冰的生长，（ii）自然启发的去冰/重新激活 灌注阶段和（iii）使用原型Bio-Thermodulator设备精确控制热力学。