Department of Mechanical Engineering University of British Columbia, 2054-6250 Applied Science Lane, Vancouver, BC, Canada V6T 1Z4.
Department of Mechanical Engineering University of British Columbia, 2054-6250 Applied Science Lane, Vancouver, BC, Canada V6T 1Z4; Department of Biology, Kwantlen Polytechnic University, Surrey, BC, Canada.
J Biomech. 2014 Jun 3;47(8):1767-76. doi: 10.1016/j.jbiomech.2014.03.038. Epub 2014 Apr 5.
A common indicator of rheological dysfunction is a measurable decrease in the deformability of red blood cells (RBCs). Decreased RBC deformability is associated with cellular stress or pathology and can impede the transit of these cells through the microvasculature, where RBCs play a central role in the oxygenation of tissues. Therefore, RBC deformability has been recognized as a sensitive biomarker for rheological disease. In the current study, we present a strategy to measure RBC cortical tension as an indicator of RBC deformability based on the critical pressure required for RBC transit through microscale funnel constrictions. By modeling RBCs as a Newtonian liquid drop, we were able to discriminate cells fixed with glutaraldehyde concentrations that vary as little as 0.001%. When RBCs were sampled from healthy donors on different days, the RBC cortical tension was found to be highly reproducible. Inter-individual variability was similarly reproducible, showing only slightly greater variability, which might reflect biological differences between normal individuals. Both the sensitivity and reproducibility of cortical tension, as an indicator of RBC deformability, make it well-suited for biological and clinical analysis of RBC microrheology.
红细胞（RBC）变形能力降低是流变功能障碍的一个常见指标。RBC 变形能力降低与细胞应激或病变有关，并可能阻碍这些细胞通过微脉管系统的运输，而 RBC 在组织的氧合中起着核心作用。因此，RBC 变形能力已被认为是流变疾病的一个敏感生物标志物。在本研究中，我们提出了一种基于 RBC 通过微尺度漏斗收缩所需的临界压力来测量 RBC 皮质张力作为 RBC 变形能力的指标的策略。通过将 RBC 建模为牛顿型液滴，我们能够区分用戊二醛固定的细胞，戊二醛浓度的差异小至 0.001%。当从不同日期的健康供体中采集 RBC 时，发现 RBC 皮质张力具有高度重现性。个体间的可变性也具有相似的重现性，仅显示出稍大的可变性，这可能反映了正常个体之间的生物学差异。皮质张力作为 RBC 变形能力的指标，其灵敏度和重现性都使其非常适合 RBC 微流变学的生物学和临床分析。
