Novel humanized mouse model developed from cord blood CD34 positive HSC and autologous iPS cell derived thymus

项目摘要/摘要 人源化小鼠，即通过以下方式支持人类免疫系统发育的免疫缺陷小鼠 人类造血干细胞(HSCs)的植入在临床前变得越来越重要 工具。然而，将HSC移植到NSG小鼠体内会导致H2限制性人类T细胞的发育 不能与自身表达的人类HLA、抗原提呈细胞和B细胞正确地相互作用 外围。已经产生了NSG-HLA转基因小鼠来解决这一问题，但人类白细胞抗原的谱系 特异性仅限于表达的那些，并且H2限制的人类T细胞继续在 小鼠胸腺。在人源化的NSG小鼠中，最强大的免疫系统是使用胎儿组织创建的， 骨髓/肝脏/胸腺(BLT)模型。BLT模型的使用允许人类T细胞在 自体胸腺，并产生强大的人类免疫系统--人类白细胞抗原限制。然而，一些人类T 小鼠胸腺中的细胞仍在发育，并受到H2的限制，对实验的解释令人困惑。在……里面 此外，使用人类胎儿组织来创造人源化的小鼠是复杂的，因为它的可用性和 由于对纸巾采购的担忧。为了提供一种替代胎儿组织模型的方法， 我们建议利用人类细胞因子转基因杂交培育的新的无性系NSG小鼠品系 用我们的裸鼠NSG-Foxn1ull(裸鼠)和CRISPR/CA直接靶向Foxn1基因的NSG小鼠 我们的新NSG库存表达了人类造血生长因子。我们将使用脐带血提取 IPS细胞创造人类胸腺结构，支持在体内发育人类白细胞抗原限制的人T细胞 来源于自体脐血造血干细胞的细胞。对于这个多PI、多学科的团队项目，我们建议 三个目标：1)建立和验证新的免疫缺陷小鼠模型，支持最佳植入 小鼠胸腺缺失情况下人胸腺组织的造血干细胞及其功能；2)人 胸腺上皮和iPS细胞产生的有机体；3)比较人类免疫系统产生的 在我们的新型号中使用BLT模型。我们的提案利用强大的新技术 创建人性化小鼠的新模型，并建立在我们25年来在生成、验证 并分享人性化小鼠的新模型。我们相信，我们的创新方法与我们的 多学科协作团队将确保开发这一亟需的临床前模型 人源化的小鼠，不依赖于使用人类胎儿组织。此外，舒尔茨博士在杰克逊 实验室，将在那里开发这些小鼠模型，促进它们快速分发到科学 社区和独特的定位，使我们能够实现此计划公告所述的目标。

PROJECT SUMMARY/ABSTRACT Humanized mice, i.e., immunodeficient mice that support the development of human immune systems by engraftment with human hematopoietic stem cells (HSCs) have become increasingly important preclinical tools. However, HSC engraftment of NSG mice results in the development of H2-restricted human T cells that cannot interact appropriately with autologous human HLA-expressing, antigen-presenting cells and B cells in the periphery. NSG-HLA transgenic mice have been generated to address this, but the repertoire of HLA specificities is restricted to only those expressed and H2-restricted human T cells continue to be generated in the murine thymus. The most robust immune system in humanized NSG mice is created using fetal tissues, the BLT (bone marrow/liver/thymus) model. Use of the BLT model permits human T cell development on an autologous thymus and generates robust HLA-restricted human immune systems. However, some human T cells still develop in the murine thymus and are H2-restricted, confounding interpretation of the experiments. In addition, the use of human fetal tissue to create humanized mice is complicated by its limited availability and by concerns surrounding procurement of the tissues. To provide an alternative to fetal tissue-based models, we propose to utilize novel athymic NSG mouse strains developed by crosses of human cytokine trangenic NSG mice with our athymic NSG-Foxn1null (nude) mouse stock and by CRISPR/Cas targeting Foxn1 directly in our new NSG stocks expressing human hematopoietic growth factors. We will use umbilical cord blood-derived iPS cells to create human thymus structures that will support in vivo development of HLA-restricted human T cells derived from autologous cord blood HSCs. For this multi-PI, multi-disciplinary team project, we propose three Aims: 1) Generate and validate new models of immunodeficient mice that support optimal engraftment of HSCs and function of human thymic tissues in the absence of murine thymus; 2) Generate and validate human thymic epithelium and organoids generated from iPS cells; 3) Compare the human immune system generated in our new models with the BLT model. Our proposal takes advantage of powerful new technologies for creating new models of humanized mice, and builds on our >25 year track record for generating, validating, and sharing novel models of humanized mice. We believe that our innovative approaches, combined with our multi-disciplinary collaborative team will ensure the development of this much-needed preclinical model of humanized mice that does not rely on use of human fetal tissues. Furthermore, Dr. Shultz is at The Jackson Laboratory where these mouse models will be developed, facilitating their rapid distribution to the scientific community and uniquely positioning us to achieve the stated goals of this program announcement.