EFFECT OF THERAPY ON SICKLE CELL HYDRATION AND SURVIVAL

网织红细胞和其他年轻红细胞对这两种细胞的贡献 镰状细胞病的溶血性和血管闭塞性方面已经变得更加 近年来很明显。同时，有效的治疗策略 （羟基脲）和有前途的实验药物（克霉唑）已成为 available.这些药物引起了根本性的但知之甚少的变化 镰状细胞的行为。在拟议的研究中，研究将 为了更好地了解时间依赖性细胞变化， 发生在循环镰状细胞，细胞年龄和HbF含量的作用， 确定这些变化，以及镰状细胞行为的改变， 这是有效治疗的结果。三种实验 将进行：1）在体外详细分析红细胞亚群， 密度分数这些实验将揭示 脱水作为年龄和HbF含量的函数，以及 这些细胞亚型与治疗的行为; 2）研究 导致年轻和成熟红细胞脱水的运输途径 在氧和脱氧条件下，以及这些活性的变化 3）在体内，多参数跟踪生物素- 标记的自体镰状细胞，以确定存活率和时间- 红细胞亚型的依赖性水化变化，细胞年龄的影响， HbF，以及有效治疗后发生的变化。观察到的 治疗前后的红细胞行为将在 镰状细胞脱水和存活的综合模型的背景下。 在该模型中，初始网织红细胞脱水依赖于 Cl共转运途径对K流出的活性，并且独立于 脱氧和HbF，而脱水的终末阶段是镰状化 HbF起着重要的作用。这些调查将 更好地了解镰状细胞病理生理学， 有效治疗导致的细胞变化，以及 提供必要的信息，以制定更好的治疗方案 战略布局

The contribution of reticulocytes and other young RBC toward both the hemolytic and vasocclusive aspects of sickle cells disease has become more apparent in recent years. At the same time, effective treatment strategies (hydroxyurea) and promising experimental agents (clotrimazole) have become available. These agents induce fundamental but poorly understood changes in the behavior of sickle cells. In the proposed research, studies will be performed to better understand the time-dependent cellular changes that occur in circulating sickle cells, the role of cell age and HbF content in determining these changes, and the modification of sickle cell behavior that occurs as a result of effective treatment. Three types of experiments will be performed: 1) Detailed in vitro analysis of RBC subpopulations in density fractions. These experiments will shed light on the extent of dehydration as a function of age and HbF content, and on changes in the behavior of these cellular subtypes with treatment; 2) Investigations of the transport pathways that lead to dehydration of young and mature RBC under oxy and deoxy conditions, and the changes in the activity of these pathways with treatment; 3) In vivo, multiparametric tracking of biotin- labeled, autologous sickle cells to determine the survival and time- dependent hydration change of RBC subtypes, the influence of cell age and HbF, and the changes that occur after effective treatment. The observed red cell behavior, before and after treatment, will be analyzed in the context of a comprehensive model of sickle cell dehydration and survival. In this model, initial reticulocyte dehydration is dependent on the activity of the CI co-transport pathway for K efflux and is independent of deoxygenation and HbF, while terminal stages of dehydration are sickling dependent, with HbF playing an important role. These investigations will provide a better understanding of sickle cell pathophysiology, define the cellular changes that occur as a result of effective treatment, and provide the information necessary to formulate improved treatment strategies.