Modulation of spinal neurodegenerative diseases in swine by stem cell grafting

 描述（由申请人提供）：特定人类疾病的大型动物模型的开发和表征及其在临床前有效性和安全性研究中的有效利用对于基于细胞替代的治疗成功过渡到临床至关重要。根据靶向疾病、细胞移植后存活的持续时间以及使用瞬时或连续免疫抑制的需要，常规使用此类模型与不同程度的技术/工艺困难相关。除了使用大型动物模型的一般考虑之外，还存在特定的限制，这取决于待研究的患病器官系统和相关的功能丧失。例如，在脊髓神经退行性疾病领域，仍然存在一些具体的挑战，包括：i）长期维持具有完全发展的截瘫表型的脊柱损伤动物，ii）用于异种移植或同种异体移植设计的可靠和安全的免疫抑制方案，和iii）用于产生同基因或异基因神经前体细胞系（NSC）的近交系部分或完全MHC匹配动物的可用性用于体内移植。此外，允许研究活动物中移植细胞存活/成熟的时间依赖性变化并在移植到单个动物受体后在差异产生的细胞群（例如，iPS衍生的NSC或胎儿组织衍生的NSC）中进行死后基因活性分析的细胞标记技术不可用。这些方案/技术的开发对于优化和验证大型临床前模型和用于前瞻性人体试验的细胞衍生方案至关重要。通过使用完全或部分MHC匹配的小型猪，我们首先提出表征在幼稚的非免疫抑制或瞬时免疫抑制的猪中移植到腰脊髓中后，建立的猪iPS或胎儿组织来源的NSC的存活、分化和基因活性谱。第二，使用充分表征的猪脊髓挫伤模型，我们将确定在脊髓移植同基因或异基因iPS和FT衍生的NSC后对运动功能恢复和相应的移植细胞存活的治疗效果。

 DESCRIPTION (provided by applicant): The development and characterization of large animal models of specific human diseases and their effective utilization in preclinical efficacy and safety studies is essential for a successful transition of cell replacement- based therapies into clinic. Depending on the disease to be targeted, the duration of post-cell transplantation survival, and the need for use of transient or continuous immunosuppression, routine use of such models is associated with a variable degree of technical/technological difficulties. In addition to general consideration in using large animal models, specific limitations exist depending on the diseased organ system and associated functional loss to be studied. In the field of spinal neurodegenerative disorders, for example, several specific challenges remain, including: i) long-term maintenance of spinally injured animals with fully developed paraplegic phenotype, ii) reliable and safe immunosuppression protocols to be used in xenograft or allogeneic grafting design, and iii) the availability of inbred partially or fully MHC-matched animals for generation of isogeneic or allogeneic neural precursor lines (NSCs) to be used for in vivo grafting. In addition, cell labeling techniques which would permit to study time dependent changes in grafted cell survival/maturation in living animals and perform postmortem gene activity profiling in differentially generated cell populations (iPS-derived NSCs or fetal tissue-derived NSCs, for example) after grafting into a single animal recipient are not available. The development of these protocols/techniques is critical for optimization and validation of large preclinical models and cell derivation protocols to be used in perspective human trials. By using fully or partially MHC- matched miniature swine, we first propose to characterize the survival, differentiation and gene activity profile of established porcine iPS or fetal tissue-derived NSCs after grafting into the lumbar spinal cord in naïve non- immunosuppressed or transiently immunosuppressed swine. Second, using well characterized porcine model of spinal contusion injury, we will define the treatment effect after spinal grafting of isogeneic or allogeneic iPS an FT-derived NSCs on the recovery of motor function and corresponding grafted cell survival.