Magnetic Separation of Liberated Islets During Isolation

描述（由申请人提供）：该提案重点关注胰岛分离的技术方面，这仍然是实施胰岛移植治疗1型糖尿病的重大障碍。在分离过程中，一旦胰岛从胰腺组织块中释放出来就将其去除，并避免密度梯度纯化的需要，这可能会导致供体胰腺的胰岛产量和效力显著增加。释放的胰岛的即时分离将最小化暴露于蛋白水解酶、活性氧中间体和与离心相关的机械应力。与腺泡组织相比，胰岛的血管丰富允许其优先富集磁珠，这反过来又允许其在过度消化、碎片化和胰岛活力丧失之前在磁场中立即分离。该提案旨在利用这些原则，在猪和人类胰岛处理的目的，最大限度地利用供体胰腺胰岛移植的磁分离为基础的技术的发展。明尼苏达大学糖尿病免疫学和移植研究所、俄亥俄州州立大学化学工程系和克利夫兰临床基金会生物医学工程系建立了跨学科合作伙伴关系，以解决以下具体目标（SA）。 SA #1：开发一种磁流分选机，用于连续、即时分离胰岛分离过程中释放的胰岛。 SA #2：比较使用传统与新型基于磁分离的处理方法分离的猪胰岛的产量和效价。 SA#3：检查人胰岛即时磁分离的可行性。成功完成拟议的研究将取代目前的胰岛分离和纯化技术。这一进展预计将1）使胰岛素不依赖于可用尸体供体库的患者数量增加三倍，以及2）允许治疗从活体供体的半胰腺分离的胰岛患者。

DESCRIPTION (provided by applicant): This proposal focuses on the technical aspects of islet isolation, which remains a substantial impediment to implementation of islet transplantation as a treatment for type 1 diabetes. Removing islets as soon as they are liberated from the pancreatic tissue mass during isolation and circumventing the need for density gradient purification is likely to result in substantially increased islet yields and potencies from donor pancreases. Instant separation of liberated islets would minimize exposure to proteolytic enzymes, reactive oxygen intermediates, and mechanical stress associated with centrifugation. The hypervascularity of islets compared with acinar tissue allows their preferential enrichment with magnetic beads, which in turn allows their immediate separation in a magnetic field before overdigestion, fragmentation, and loss of islet viability ensues. This proposal seeks to exploit these principles in the development of magnetic separation-based techniques for porcine and human islet processing for the purpose of maximizing the utilization of donor pancreases for islet transplantation. The University of Minnesota Diabetes Institute for Immunology and Transplantation, the Ohio State University Department of Chemical Engineering and the Cleveland Clinic Foundation Department of Biomedical Engineering, have established an interdisciplinary partnership to address the following Specific Aims (SA). SA#1: To develop a magnetic flow sorter for continuous and instant separation of islets liberated during the islet isolation process. SA#2: To compare the yield and potency of porcine islets isolated using conventional versus novel, magnetic separation-based processing methods. SA#3: To examine the feasibility of instant magnetic separation of human islets. The successful completion of the proposed studies will supercede current islet isolation and purification techniques. This advance is expected to 1), increase threefold the number of patients rendered insulin independent from the available cadaver donor pool and 2), to permit treatment of patients with islets isolated from a hemi-pancreas from living donors.