To determine the number and intensity of phosphatidylserine (PS) expression of the red blood cells (RBCs), fragmented RBCs, and RBC-derived microparticles (RMPs) in patients with β-thalassemia/hemoglobin (Hb)E. We used flow cytometry to determine the number and levels of PS expression. The number of PS-exposing RBCs was statistically significantly higher (P <.001) than that of PS-exposing fragmented RBCs or RMPs. In contrast, the intensity of PS expression was significantly higher (P <.001) in RMPs than in RBCs or fragmented RBCs. Our study showed a trend of association between RBC distribution width (RDW) and both the number of fragmented RBCs and RMPs and their intensity of PS expression. In β-thalassemia/HbE, PS-exposing RBCs, fragmented RBCs, and RMPs all differed in their numbers and their intensity of PS expression. The effects of these differences among PS-exposing populations on the pathophysiology of the disease require further investigation.

In the past few years, interest has increased in cell-derived microparticles (MPs), which are defined by their size of from 0.1 to 1 μm, and can be derived from various cell types, including endothelial cells, leukocytes, red blood cells (RBCs), and platelets. These MPs carry negatively charged phosphatidylserine (PS) on their surfaces and proteins packaged from numerous cellular components. MPs that have been shed by the body can play important roles in the pathophysiology of diseases and can affect various biological systems. Among these systems, the immune components have been shown to be modulated by MPs. Therefore, understanding the roles of MPs in the immune system is crucial to developing alternative therapeutic treatments for diseases. This review describes the effects of MPs on various immune cells and provides plausible potential applications of the immune-modulating properties of MPs in clinical medicine.

Cell-derived microparticles (MPs) are small fragments released from various cells when they are activated or undergo apoptosis. In the field of transfusion medicine, a number of studies have documented increased levels of MPs in blood products, which have been associated with multiple factors, including donor variability, blood component processing, and storage. In addition, transfusions that contain high levels of MPs are linked to posttransfusion complications. Considering the clinical importance of MP levels, transfusion laboratories should routinely screen blood products for them. However, this practice is not yet applied routinely, perhaps in part because of a lack of understanding of how to apply MP data to transfusion medicine. We describe the methods used to quantitate MPs in blood components and discuss the application of these quantitative data in routine transfusion laboratories in order to manage quality, improve the outcomes of transfusions, and minimize their complications.