The red blood cell (RBC) deformability test is the measurement of the ability of RBCs to adapt their shape to the flow conditions. The major determinants of RBC deformability include cell shape, composition of the cell membrane and cytoskeleton, and internal viscosity (mean cell hemoglobin concentration). RBC deformability is primarily regulated by the composition and arrangement of the cell membrane. In cancer patients, chemotherapy and hematopoietic stem transplantation (HSCT) affect the bone marrow microenvironment, which may alter RBC production and deformability. We aimed to evaluate the change in RBC deformability during HSCT. Blood samples were obtained from patients who underwent HSCT. Eleven children were enrolled in this study. RBC deformability was measured with a microfluidic ektacytometer (RheoScan-D, RheoMeditech, Seoul, Korea). All analyses were completed within 24 hours after blood collection. The elongation index of the erythrocytes was measured. The elongation index of RBCs gradually increased from day 5 to day 30 after HSCT. RBC deformability may reflect the bone marrow microenvironment of the patient during HSCT. Further studies investigating the correlation between RBC deformability and the prognosis of HSCT are needed.

红细胞 (RBC) 变形能力测试是测量红细胞使其形状适应流动条件的能力。红细胞变形性的主要决定因素包括细胞形状、细胞膜和细胞骨架的组成以及内部粘度（平均细胞血红蛋白浓度）。红细胞变形能力主要受细胞膜的组成和排列调节。在癌症患者中，化疗和造血干移植（HSCT）会影响骨髓微环境，这可能会改变红细胞的产生和变形能力。我们的目的是评估 HSCT 期间红细胞变形能力的变化。血液样本取自接受 HSCT 的患者。十一名儿童参加了这项研究。使用微流控细胞仪（RheoScan-D，RheoMeditech，首尔，韩国）测量红细胞变形能力。所有分析均在采血后 24 小时内完成。测量红细胞的伸长指数。HSCT后第5天至第30天红细胞伸长指数逐渐升高。红细胞变形能力可能反映HSCT时患者的骨髓微环境。需要进一步研究红细胞变形能力与 HSCT 预后之间的相关性。