Understanding stem cell heterogeneity and niche function in intestinal regeneration after irradiation

项目摘要 放射诱导的胃肠道综合征(RIGS)是由于剂量依赖的、细胞杀伤作用的 对肠道隐窝细胞的辐射。目前还没有批准的医学对策来缓解 钻机。当活跃的Lgr5干细胞被有效地消融时，再生从储备中出现，处于静止状态 抗辐射的祖细胞/干细胞。这两个祖先种群之间的确切关系 (抗辐射和对辐射敏感)仍未定义，需要更多信息来开发治疗方法 用于钻机和其他疾病。迫切需要一种不偏不倚的方法来充分描述 正常和再生肠道中的细胞，与先验知识或纯化分析无关。工作地点： 我们的实验室和ISCC已经证明了基质间充质细胞和其他利基细胞在 调节ISC的动态平衡和再生，但尚不存在全面的调控模式。矩阵 蛋白质也是生态位的一部分，我们已经能够生长肠样和人类肠道 组织特异性水凝胶中的有机类化合物。我们的研究人员和合作者已经开发出新的R-响应蛋白 和Wnt激动剂用于体内给药，但用于治疗钻机的最佳组合尚未确定。 因此，对ISCs和NICE细胞之间的串扰信号和刺激模型有了充分的了解 或取代肠道间充质干细胞，是钻机治疗进展所必需的。与其他成员合作 关于ISCC，我们提出了两个具体目标。目的1.肠隐窝的异质性如何 细胞和邻近的基质细胞在辐射后会发生变化吗？我们将分析高纯度的隐窝上皮细胞 以及使用新型多重scRNA-seq平台照射前后的基质细胞，并应用 开发分层结构和监管模型的计算工具(MetaVIPER)。目标2.可以 使用利基因子或干细胞治疗可以减轻辐射或炎症性损伤 肠子？我们将研究减轻钻机重量的新因素组合，然后使用组织特异性水凝胶 和新的因子和细胞在体外生长和体内移植人肠道有机化合物治疗结肠炎和 放射性直肠炎。总体而言，这项提案将使用哥伦比亚大学/爱因斯坦公司开发的新技术来推动 ISCC的合作使命是再生人类的肠道。

Project Summary The radiation-induced gastrointestinal syndrome (RIGS) results from dose-dependent, cytocidal effects of radiation on intestinal crypt cells. There are currently no approved medical countermeasures to alleviate the RIGS. While active Lgr5+ stem cells are efficiently ablated, regeneration emerges from reserve, quiescent progenitor/stem cells that are radio-resistant. The exact relationship between these two progenitor populations (radio-resistant and radio-sensitive) remains undefined, and more information is needed to develop therapies for RIGS and other disorders. An unbiased approach is critically needed to fully characterize the diversity of cells in normal and regenerating intestine, independent of prior knowledge or purification assays. Work from our lab and the ISCC has demonstrated a key role for the stromal mesenchyme and other niche cells in modulating ISC homeostasis and regeneration, but a comprehensive regulatory model does not exist. Matrix proteins are also part of the niche, and we have been able to grow both enteroids and human intestinal organoids in tissue-specific hydrogels. Our investigators and collaborators have developed novel R-spondin and Wnt agonists for in vivo delivery but the optimal combinations for treatment of RIGS have not been defined. Thus, a full understanding of the cross-talk signals between ISCs and niche cells, and models for stimulating or replacing intestinal ISCs, is needed for advances in therapy for RIGS. In collaboration with other members of the ISCC, we are proposing two specific aims. Aim 1. How does the heterogeneity of intestinal crypt cells and adjacent stromal cells change after radiation? We will analyze highly pure crypt epithelial cells and stromal cells using a novel multiplex scRNA-seq platform before and after radiation, and apply computational tools (metaVIPER) to develop a hierarchical structure and regulatory model. Aim 2. Can therapy with niche factors or stem cells be used to mitigate radiation or inflammatory injury to the intestine? We will study novel combinations of factors to mitigate RIGS, and then use tissue-specific hydrogels and novel factors and cells to grow in vitro and transplant in vivo human intestinal organoids to treat colitis and radiation proctitis. Overall, this proposal will use novel technology developed at Columbia/Einstein to advance collaboratively the ISCC mission to regenerate the human intestine.