Dissecting the Functional Role of Monocytes in B-cell Acute Lymphoblastic Leukemia Survival

《科学文摘》 骨髓微环境很可能在促进B细胞急性淋巴母细胞分化中起重要作用 白血病(B-ALL)的生存、进展和逃避治疗。我们的初步研究使用了单细胞 全面定位人初级B-ALL骨髓免疫图谱的方法 在疾病的三个不同阶段：诊断、缓解和复发的微环境。 重要的是，我们发现了白血病相关单核细胞亚群在B-ALL存活率中的作用， 证明诊断时单核细胞丰度可预测儿童和成人B-ALL患者 结果。使用基于三维(3D)微流体的器官类型设备，我们证明了人类B-ALL 原始细胞改变血运微环境促进单核细胞分化和白血病耗竭 Ph+B-ALL动物模型中的相关髓系细胞在体内可延长疾病缓解时间。这个项目 将确定非经典单核细胞在支持B-ALL生存方面的确切来源和功能， 最终，靶向支持白血病的单核细胞，以提高现有ALL治疗的疗效。要实现 因此，我们将使用双光子实时成像来评估白血病患者中非经典单核细胞的行为。 利基市场。然后我们将利用缺乏非经典单核细胞的小鼠品系，以及建立的 单细胞图谱方法评估单核细胞丰度对血管化血管重塑的影响 活体内的白血病利基。我们将扩大我们对初级儿童B-ALL大队列的流式细胞仪分析 患者样本以建立单核细胞丰度、单核细胞分化状态和 与儿科白血病专家Karen Rabin博士(贝勒)合作的患者治疗结果 大学/德克萨斯儿童医院)和Charles Mullight an(圣裘德儿童医院)。最后，小鼠和 人类异种移植临床前体内B-ALL平台确定耗竭性白血病支持的影响 单核细胞(抗CSF1R治疗)联合常规B-ALL化疗对B-ALL生存率的影响。 这些发现最终将为结合抑制CSF1R和现有的B-ALL的临床试验提供基础 治疗学。这份建议概述了我的职业发展计划，以获得必要的准备 转变为一名成功的独立调查员。我的博士后导师，Iannis Aifantis博士，完全 支持我独特的研究计划。我正在接受非经典单核细胞生物学专家的培训(Dr。 Hedricks，La Jolla免疫学研究所)，活体双光子显微镜(David Fooksman，Albert 和单细胞生物信息学(纽约大学应用生物信息学实验室齐里戈斯博士)将提供 完成我的长期科学目标所必需的知识。总的来说，拟议的研究和 职业发展计划将产生对儿科基于免疫的治疗产生重大影响的数据 并为我作为一名独立研究人员的未来研究提供了基础。

Scientific Abstract The bone marrow microenvironment most likely plays a significant role in promoting B-cell acute lymphoblastic leukemia (B-ALL) survival, progression, and escape from treatment. Our preliminary studies utilized single-cell profiling approaches to comprehensively map the primary human B-ALL bone marrow immune microenvironment throughout three distinct stages of the disease: diagnosis, remission and relapse. Importantly, we uncovered a role for leukemia-associated monocyte subpopulations in B-ALL survival, demonstrating that monocyte abundance at diagnosis is predictive of pediatric and adult B-ALL patient outcomes. Using a three-dimensional (3D) microfluidics-based organotypic device, we show that human B-ALL blasts alter a vascularized microenvironment to promote monocytic differentiation and depletion of leukemia associated myeloid cells in Ph+ B-ALL animal models leads to prolonged disease remission in vivo. This project will determine the precise origins and function of nonclassical monocytes in supporting B-ALL survival and, ultimately, target leukemia-supporting monocytes to enhance the efficacy of existing ALL therapy. To achieve this, we will use two-photon live-imaging to assess nonclassical monocytes' behavior within the leukemic niche. We will then take advantage of murine strains lacking nonclassical monocytes, as well as established single-cell profiling approaches, to assess monocyte abundance's impact on the remodeling of a vascularized leukemic niche in vivo. We will expand our flow cytometric analysis of large cohorts of primary pediatric B-ALL patient samples to establish the association between monocyte abundance, monocyte differentiation state, and patient treatment outcome through a collaboration with pediatric leukemia experts, Drs. Karen Rabin (Baylor University/Texas Children's Hospital) and Charles Mullighan (St Jude Children's Hospital). Finally, murine and human xenograft pre-clinical in vivo B-ALL platforms to determine the impact of depleting leukemia-supporting monocytes (anti-CSF1R therapy) in combination with conventional B-ALL chemotherapy on B-ALL survival. These findings will ultimately provide the basis for clinical trials combining CSF1R inhibition with existing B-ALL therapeutics. This proposal outlines my career development plan for obtaining the necessary preparation to transition into a successful independent investigator. My postdoctoral supervisor, Dr. Iannis Aifantis, fully supports my distinct research program. My ongoing training with experts in nonclassical monocyte biology (Dr. Hedricks, La Jolla Institute for Immunology), live in vivo two-photon microscopy (David Fooksman, Albert Einstein) and single-cell bioinformatics (Dr. Tsirigos, NYU Applied Bioinformatics Laboratories) will provide the essential knowledge to accomplish my long-term scientific goals. Collectively, the proposed research and career development plans will generate data with a significant impact on immune-based therapies in pediatric leukemia and provide the basis of my future research as an independent researcher.