FILTERABILITY OF MIXTURES OF SICKLE AND NORMAL ERYTHROCYTES FOR TRANSFUSION

红细胞输血长期以来一直是，目前仍然是一个 镰状细胞病管理的组成部分 （SCD）。 明智地使用血液既可以挽救生命， 和延长生命的各种临床环境。 输血有两种广泛的适应症， SCD，维持氧气的携带能力， 血液和稀释循环的含HbS的细胞。 后者可以通过直接 输血的稀释作用，但也其次 通过抑制骨髓和减少生产 能够镰刀形的细胞。 红细胞交换提供了许多潜在的优势 而不是简单的输血， SCD的并发症，特别是如果担心 引起循环过载或引起高粘滞性 国家，这实际上可能会加剧倾向， 通过阻碍毛细血管运输而形成镰刀状。 的指导方针 换血疗法应来源于 了解镰状细胞的流变学行为。 变形不良的红细胞引起的微血管闭塞 被认为是SCD的关键病理生理事件。 因此，我们研究了镰刀的变形能力， (SS)细胞及其与正常（AA）细胞的混合物， 通过镍网的过滤性。 我们也 研究了密集SS细胞和密集SS 网织红细胞的整体变形性。 本研究 发现SS和AA的混合物的过滤 红细胞几乎以线性方式受到两者的影响。 SS红细胞%和致密细胞%，致密细胞 对这些混合物的过滤的损害是 与无致密细胞的SS红细胞相似。 过滤无致密细胞的SS细胞和 AA细胞占60%以上，与 正常红细胞 这些结果表明，交换 输血治疗的目的应是减少致密细胞， 在保持SS水平的同时， 细胞占总细胞的比例低于40%。 我们的研究结果还 表明密集的SS网织红细胞 与变形能力降低有关。 我们的数据，使用 自动网织红细胞分析仪显示， 高荧光网织红细胞的升高， SCD患者，这表明 未成熟网织红细胞的再生。 的利益 因此，交换输血不仅是由于 直接稀释效应，但也由于抑制SS 网状细胞 这些研究可以提供实用的 输血交换计划指南， 镰状细胞的流变学行为。

RBC transfusion has long been and currently remains an integral part of the management of sickle cell disease (SCD). The judicious use of blood can be both life-saving and life-prolonging in variety of clinical settings. There are two broad indications for blood transfusion in SCD, maintenance of the oxygen-carrying capacity of the blood and dilution of the circulating HbS-containing cells. The latter may be accomplished both by the direct dilutional effect of transfused blood but also secondarily by suppression of the bone marrow and decreased production of cells capable of sickling. Erythrocyte exchange offers numerous potential advantages over simple transfusion for the management of certain complications of SCD, especially if there is concern of causing circulatory overload or inducing a hyperviscosity state, which may actually exacerbate the propensity to sickle by retarding capillary transit. Guidelines from exchange transfusion therapy should be derived from an understanding of the rheological behavior of sickle cells. Microvascular occlusion by poorly deformable erythrocytes is believed to be the key pathophysiologic event in SCD. We, therefore, investigated the deformability of sickle (SS) cells and their mixture with normal (AA) cells in terms of filterability through nickel mesh. We also examined the role of dense SS cells and dense SS reticulocytes in overall deformability. In this study, we found that the filtration of mixtures of SS and AA erythrocytes was affected in almost linear fashion by both the %SS erythrocytes and %dense cells, and that dense cells impaired the filtration of these mixtures about 25 times as much as the of SS erythrocytes with no dense cells did. Filtration of mixtures of SS cells with no dense cells and AA cells of more than 60% was almost the same as that of normal erythrocytes. These results suggest that exchange transfusion therapy should aim at decreasing dense cells as much s possible, as well as at keeping the level of SS cells to the total cells below 40%. Our results also indicate the possibility that dense SS reticulocytes involved in reduced deformability. Our data, using an automated reticulocyte analyzer, showed that the proportion of high fluorescence-reticulocytes was elevated in the patients with SCD, which indicated the increased regeneration of immature reticulocytes. The benefit of exchange transfusion, therefore, can be not only due to direct dilution effect, but also due to suppression of SS reticulocytes. These studies can provide the practical guideline for exchange transfusion program based on the rheological behavior of sickle cells.