NHLBI CLINICAL INVESTIGATOR AWARD PROGRAM

在分化过程中发生的事件沿着 将研究巨核细胞-血小板轴，重点是分离和 增强巨核细胞增殖的因子的表征， 成熟 为便于巨核细胞制剂的筛选 集落刺激因子（meg-CSA），一种快速定量检测细胞内 体外巨核细胞生长将使用巨核细胞-血小板 骨髓液中的膜特异性放射性标记单克隆抗体 培养技术 将使用半固体培养基骨髓培养试验， 使液体测定标准化，并允许评价个体 殖民地 将在各种细胞中寻找meg-CSA的丰富来源 上清液、细胞提取物和患者样本，以及单个因子 然后通过常规的生物化学分离技术分离。 多克隆和单克隆抗体将针对分离的 因素 这些抗体将用于促进进一步的分离， 并开发用于患者研究的放射免疫测定法。 分离 meg-CSA将被表征为结构，来源的特定细胞， 和靶细胞。 将检测凝血蛋白和成熟血小板 在巨核细胞生成的反馈调节中发挥作用。 严格 巨核细胞生成中一个离散调节因子的表征，和 在患者中定量的能力，将扩大我们对 巨核细胞生成的特异性控制的临床疾病 不足或无效，并导致血小板减少症，或 尽管红细胞和白色血数量正常，但仍有血小板增多症 细胞

The events which occur during differentiation along the megakaryocyte-platelet axis will be studied, with emphasis on isolation and characterization of factors which enhance megakaryocyte proliferation and maturation. To facilitate screening of preparations of megakaryocyte colony stimulating factors (meg-CSAs), a rapid quantitative assay for in vitro megakaryocyte growth will be developed using megakaryocyte-platelet membrane specific radiolabeled monoclonal antibodies in a liquid marrow culture technique. Semi-solid medium marrow culture assays will be used to standardize the liquid assay, and to allow evaluation of individual colonies. Rich sources of meg-CSA(s) will be sought among various cell supernatants, cell extracts and patient samples, and individual factors then will be isolated by conventional biochemical separation techniques. Polyclonal and monolonal antibodies will be raised against isolated factors. These antibodies will be used to facilitate further isolations, and to develop radioimmunoassays to be used in patient studies. Isolated meg-CSA(s) will be characterized as to structure, specific cells of origin, and target cells. Coagulation proteins and mature platelets will be tested for a role in feedback regulation of megakaryopoiesis. Rigorous characterization of one discrete regulatory factor in megakaryopoiesis, and the ability to quantitate it in patients, will expand our understanding of clinical disorders in which specific controls of megakaryopoiesis are either inadequate or ineffective and lead to thrombocytopenia or thrombocytosis despite normal numbers of red blood cells and white blood cells.