Developing a bank of purified myeloid progenitor cells as a bridging therapy for transient pancytopenia resulting from radiation injury

摘要 即使暴露在中等水平(&lt；3Gy.)的电离辐射下也会导致严重的 全血细胞减少症，将患者视为意外暴露的受害者，对 感染和失控出血。意外暴露与放射治疗的区别在于 生物剂量测定(例如，辐射类型、剂量和剂量率)通常是不确定的；因此， 改善辐射影响的最佳治疗方案并不是马上就能显现出来。 因此，意外电离辐射暴露的受害者将从桥接中受益 穿越中性粒细胞减少和血小板减少的延长时期直到最佳状态的治疗 可以确定医疗护理的进程。 铯健康公司建议从死者身上建立髓系祖细胞(MPC)库 供者骨髓(BM)。该策略使用了商业上可用的免疫磁力 选择试剂和临床规模的闭合系统半自动设备以进行特定的选择 在定义细胞表面标志物CD34+CD38+的基础上，从整个骨髓中分离出MPC。建议数 第一阶段的研究建立在我们之前的成功基础上，选择了大量(&gt；1.5亿) 来自器官捐赠者骨髓的干细胞和祖细胞。我们将评估选择的组合， 耗竭和消融在不污染T细胞的情况下纯化MPC长期再生干细胞 用于预防移植物抗宿主疾病的细胞。这些细胞将在体外和体内进行验证 小鼠异种移植重建短期天然免疫的研究。 这项研究计划的整体产品将是一个令人信服的临床前一揽子计划，以证明 明确的研究支持FDA根据动物规则批准一种新的辐射/核 大规模伤亡医学对策搭桥治疗。这两家公司未来的商业可行性 医疗对策和民用得到增强，最高可降低5倍的成本 制造业与当前技术的比较。

ABSTRACT Exposure to even moderate levels (<3 Gy) of ionizing radiation can result in severe pancyotopenia, placing patients as wells as victims of accidental exposure at high risks for infection and uncontrolled hemorrhaging. Accidental exposure differs from radiation therapy in that biodosimetry (e.g., type of radiation, dose and dose rate) is often uncertain; consequently, the optimal treatment regimen to ameliorate the effects of radiation is not immediately evident. Therefore, victims of accidental ionizing radiation exposure would benefit from bridging therapies to traverse extended periods of neutropenia and thrombocytopenia until the optimal course of medical care can be determined. Ossium Health proposes to develop a bank of myeloid progenitor cells (MPC) from deceased donor bone marrow (BM). The strategy employs commercially available immunomagnetic selection reagents and clinical-scale closed-system semi-automated devices to specific select MPC from whole BM based on defining cell surface markers CD34+CD38+. The proposed Phase I studies build on our previous success with selecting large numbers (>150 million) of stem and progenitor cells from organ donor BM. We will evaluate combinations of selection, depletion and ablation to purify MPC without contaminating T cells long-term repopulating stem cells to prevent graft versus host disease. The cells will be validated in vitro and in vivo in a mouse xenotransplantation study to evaluate reestablishment of short-term innate immunity. The overall product of this research program will be a compelling preclinical package to justify definitive studies to support FDA approval under the Animal Rule for a novel radiation/nuclear mass casualty medical countermeasure bridging therapy. Future commercial viability for both medical countermeasures and civilian uses is enhanced by the up to 5-fold lower cost for manufacturing compared to current technologies.