Clinical Pathology Department, Faculty of Medicine, Suez Canal University, Ismaillia, Egypt.
Blood Transfus. 2010 Jan;8(1):28-35. doi: 10.2450/2009.0077-09.
Currently platelet concentrates (PC) are collected using different synthetic materials and different centrifugation/leucocyte-removal processes. Upon exposure to artificial surfaces and high centrifugation forces, blood cells can undergo various levels of stress-induced, cellular activation/fragmentation and release reactions which may not only influence the extent of the platelet storage lesion but may also contribute to poor clinical effectiveness of the PC and transfusion reactions.
An array of assays, used for quality control of PC, was performed in two different groups of PC prepared from random donor plasma on days 1, 3 and 5 of storage. The group 1 PC were not leucoreduced while the group 2 PC underwent prestorage leucoreduction using a PL50E filter. As current recommendations for the evaluation of PC include the measurement of platelet activation, in this study CD62P on platelet membrane was measured. Furthermore, in vitro studies indicate that sHLA antigens may modulate immune competent cell function so, the presence of sHLA-1 in blood components is considered a marker of immunological reactivity and this, too, was measured.
The levels of CD62P and sHLA-1 were significantly lower in leucoreduced PC than in non-leucoreduced ones. However, the overall rate of increase of sHLA-1 during storage was faster in the leucoreduced group of PC. No significant differences were detected regarding other assays of quality.
Based on our findings, leucoreduced PC differ from non-leucoreduced ones in terms of some specific markers such as CD62P as a marker of platelet activation and sHLA-1 as a marker of immunological reactivity. Pre-storage leucofiltration, followed by storage in currently used plastic bags is a safe procedure for PC for up to 5 days. The available leucoreduction technologies are not, however, sufficiently robust to completely abrogate transfusions reactions, and improvements are required to reach the goal of optimised yield and minimal transfusion reactions with platelet therapy.
目前血小板浓缩物（PC）是使用不同的合成材料和不同的离心/白细胞去除过程收集的。暴露于人工表面和高离心力下，血细胞会经历不同程度的应激诱导的细胞激活/碎裂和释放反应，这不仅会影响血小板储存损伤的程度，还可能导致 PC 和输血反应的临床效果不佳。
在储存的第 1、3 和 5 天，对两组来自随机供体血浆的 PC 进行了一系列用于 PC 质量控制的检测。组 1 的 PC 未进行白细胞减少处理，而组 2 的 PC 使用 PL50E 过滤器进行了储存前白细胞减少处理。由于目前对 PC 的评估建议包括血小板激活的测量，因此在本研究中测量了血小板膜上的 CD62P。此外，体外研究表明，sHLA 抗原可能调节免疫活性细胞的功能，因此，血液成分中存在 sHLA-1 被认为是免疫反应性的标志物，这也进行了测量。
白细胞减少处理的 PC 中 CD62P 和 sHLA-1 的水平明显低于未白细胞减少处理的 PC。然而，在白细胞减少处理的 PC 组中，sHLA-1 在储存过程中的总体增加速度更快。在其他质量检测方面没有发现显著差异。
根据我们的发现，白细胞减少处理的 PC 在某些特定标志物方面与未白细胞减少处理的 PC 有所不同，例如 CD62P 作为血小板激活的标志物和 sHLA-1 作为免疫反应性的标志物。在目前使用的塑料袋中进行储存前白细胞过滤是一种安全的 PC 处理方法，最长可达 5 天。然而，现有的白细胞减少处理技术还不够强大，无法完全消除输血反应，需要改进以达到优化血小板治疗的产量和最小化输血反应的目标。
