The Origin and Function of Lung Megakaryocytes

肺巨核细胞的起源和功能

• 批准号: 10677191
• 负责人: Alison Claire Livada
• 金额: $ 5.27万
• 依托单位: UNIVERSITY OF ROCHESTER
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-15 至 2027-09-14
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10677191
• 关键词: Acceleration; Adult; Automobile Driving; Biological Models; Blood; Blood Platelets; Blood Vessels; Bone Marrow; Cardiovascular Diseases; Cells; Colony-Forming Units Assay; Communicable Diseases; Data; Development; Disease; Dyes; Embryo; Environment; Flow Cytometry; Future; Hematopoiesis; Hematopoietic; Hematopoietic stem cells; Heterogeneity; Homeostasis; Immune; Immune response; Immunofluorescence Immunologic; Immunological Models; Immunology; Immunophenotyping; In Vitro; Infection; Inflammation; Inflammatory; Label; Large Megakaryocyte; Lung; Lung Capacity; Lung diseases; Malaria; Megakaryocytes; Megakaryocytopoieses; Methods; Modeling; Morphology; Mus; Oropharyngeal; Parents; Phenotype; Physicians; Physiological; Ploidies; Population; Process; Production; Proto-Oncogene Protein c-kit; Reporter; Research; Role; SLAM protein; Scientist; Sorting; Source; Spleen; Sterility; Techniques; Testing; Thrombocytopenia; Thrombopoiesis; Thrombosis; Tissues; Training; Transplantation; Vascular Diseases; career; career development; daughter cell; direct application; experimental study; improved; in vivo; insight; irradiation; migration; mouse model; novel; novel strategies; pulmonary function; reconstitution; self-renewal; trafficking; transcriptome sequencing

Abstract Platelet parent cells are megakaryocytes (Mks). Studies have historically focused on Mk derived platelet production in the bone marrow (BM) (1). More recently, platelet-producing Mks have been shown to be present in the lung, and our lab and others have described an immune modulatory phenotype of lung Mks (2-4). The recent identification of a low ploidy, immune differentiated BM Mk sub-population (5) highlights the relationship that lower Mk ploidy may correlate with a more immune differentiated Mk. We refer to the development of a Mk immune modulatory sub-population as Mk immune differentiation. The origin of lung Mks and mechanisms of their immune differentiation remain unknown. It is assumed, without experimental evidence, that lung Mks are ‘seeded’ from immature circulating BM Mks. Lefrancais et al. showed the presence of GFP+ Mks in the lung vasculature when a mTmG lung was transplanted to a PF4-Cre-mTmG recipient. The authors argued that the presence of GFP+ intravascular lung Mks demonstrated an extra-pulmonary source. However, intravascular and extravascular lung Mks have morphological and perhaps functional differences, and extravascular lung Mks make up about 70% of all lung Mks. Thus, the majority of circulating Mks would have to leave the blood and tissue migrate to become lung resident. Without direct evidence for this trafficking, the definitive origin of extravascular lung Mks remains unknown, but may have a major impact on their immune differentiation. I hypothesize that extravascular lung Mks derive from a local hematopoietic progenitor pool independent of BM megakaryopoiesis. I will test this hypothesis by using complementary methods, including irradiation and transfer experiments, lineage tracing, and in vitro colony forming unit assays. The impact of Mk immune differentiation on the platelet pool is still not clear. Lung Mks make platelets, although the relative proportion of lung derived platelets remains controversial (4, 6). Emerging evidence from studies of platelet heterogeneity are beginning to suggest that platelet subsets may have functional significance. I hypothesize that lung resident Mks contribute to an immune-differentiated platelet sub-population. To test this hypothesis, I will use a novel strategy to identify lung derived platelets using oropharyngeal CFSE administration in physiologic and thrombocytopenic conditions such as PF4-Cre-iDTR mice and nonlethal murine malaria. Results from my proposed studies will contribute to an improved understanding of immune differentiated megakaryopoiesis, and its role in coordinated immune responses and platelet immune phenotypes, with direct applications to many vascular inflammatory diseases.

抽象的 血小板母细胞是巨核细胞（MKS）。研究从历史上一直集中在MK衍生的血小板上 骨髓（BM）（1）的产生。最近，已经显示出产生血小板的MK 在肺中，我们的实验室和其他实验室描述了肺MK的免疫调节表型（2-4）。 最近鉴定出低倍性，免疫分化的BM MK亚群（5）突出了这种关系 该较低的MK倍性可能与更免疫分化的MK相关。我们指的是MK的发展 免疫调节子群作为MK免疫分化。肺MK的起源和机制 它们的免疫分化仍然未知。 没有实验证据，假定肺MK是从未成熟循环的BM中“播种”的 MKS。 Lefrancais等。在MTMG肺为 移植到PF4-CRE-MTMG受体。作者认为GFP+血管内肺的存在 MKS展示了一个肺外来源。但是，血管内和血管外肺MK具有 形态学和可能的差异，血管外肺MK占所有肺的70％ MKS。这，大多数循环的MK必须离开血液和组织迁移至肺 居民。没有直接证据表明这种贩运，血管外肺MK的明确起源仍然存在 未知，但可能会对其免疫定位产生重大影响。我假设该血管外肺 MKS源自BM Megakaryopiesis的局部造血祖细胞池。我会测试这个 通过使用互补方法，包括辐照和转移实验，谱系跟踪，假设， 和体外菌落形成单元分析。 MK免疫分化对血小板池的影响尚不清楚。肺MK虽然是血小板的 肺部衍生血小板的相对比例仍然存在争议（4，6）。从研究 血小板异质性开始表明血小板子集可能具有功能意义。我 假设肺居民MK有助于免疫分化的血小板亚群。测试这个 假设，我将使用一种新型策略使用口咽CFSE给药来识别肺部衍生的血小板 在生理和血小板减少症状中，例如PF4-CRE-IDTR小鼠和非致死鼠疟疾。 我提出的研究的结果将有助于提高对免疫分化的理解 Megakaryopoiesis及其在协调的免疫调查和血小板免疫调查中的作用，直接 对许多血管炎症性疾病的应用。