Signaling properties of driver mutations in clonal hematopoiesis of indeterminate potential (CHIP) as targets for diagnostics and therapeutic intervention

诱导克隆扩增的造血干细胞体细胞突变通常是在人类衰老过程中获得的。潜在不确定克隆造血（CHIP）是恶性血液病和心血管疾病发展的重要危险因素，并与全因死亡率增加相关。越来越多的证据表明，炎症失调有助于克隆扩增和相关的合并症，如先前感染的炎症、先前存在的合并症或随着年龄增长而发生的低度炎症（炎症）。chip特异性分子特征可能是诊断和开发特异性治疗的重要靶点。在这个项目中，我们的目标是用先进的多组学单细胞分析工具识别CHIP相关的信号通路和表面标记物的表达模式。在这项建议的初步工作中，我们分析了600多名接受干细胞白血病摘除术的患者动员干细胞产品中的CHIP突变。此外，我们建立了一个特定的生物信息学工具集在这个项目的分析。多组学单细胞分析将用于识别跨不同CHIP突变和细胞类型的解除调控的信号通路和表面标记模式（CITE-Seq）。随后，我们将在脐带血CD34+造血干细胞（HSC）中过表达和敲除chip相关的表达模式/信号通路，并在体外和体内分析信号/炎症基因的修饰是否会导致候选驱动突变。对于具有特异性抑制剂的顶级调控途径/靶点，我们将分析体外药物反应，并进行体内异种移植研究，以评估各自药物优先根除CHIP克隆的潜力。综上所述，该项目将揭示可能用于诊断和潜在治疗应用的途径/调控基因，以抑制CHIP克隆。

Somatic mutations in hematopoietic stem cells which induce clonal expansion are commonly acquired during human aging. Clonal hematopoiesis of indeterminate potential (CHIP) constitutes an important risk factor for the development of hematological malignancies and cardiovascular disease and is associated with an increased all-cause mortality. A growing body of evidence suggest that dysregulated inflammation contributes to clonal expansion and associated comorbidities such as inflammation from previous infections, pre-existing comorbidities or low-grade inflammation occurring with aging (inflammaging). CHIP-specific molecular features might be important targets for diagnostics and development of specific therapies. In this project we aim to identify CHIP associated signaling pathways and surface marker expression patterns with advanced multi-omics single cell analysis tools. In preliminary work for this proposal we analyzed CHIP mutations in mobilized stem cell products from more than 600 patients undergoing stem cell leukapheresis. Also, we established a specific bioinformatics tool set for the analyses in this project. Multi-omics single cell analyses will be used to identify deregulated signaling pathways and surface marker patterns (CITE-Seq) across diverse CHIP mutations and cell types. Subsequently, we will overexpress and knockout CHIP-associated expression patterns/signaling pathways in CD34+ hematopoeitic stem cells (HSC) from cord blood and analyse in vitro and in vivo whether modification of signaling/inflammatory genes phenocopies candidate driver mutations. For the top-regulatory pathways/ targets for which specific inhibitors are available we will analyze in vitro- drug responses and will perform in vivo xenograft transplantation studies to evaluate the potential of the respective drugs to preferentially eradicate CHIP clones. Taken together, this project will reveal pathways/regulatory genes which might be used for diagnostics and potentially for therapeutic applications to suppress CHIP clones.